<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:01a198af-cd4c-7b06-b9a2-4c57ded1174d,g:e28dd998-19df-4d3f-a22a-5ba066095fde-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/CondensedConsolidatedStatementsofOperations" xlink:type="simple" xlink:href="wynn-20260930.xsd#CondensedConsolidatedStatementsofOperations"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/CondensedConsolidatedStatementsofOperations" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_01a198af-cefe-734d-a995-89b9561344b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_StatementTable_01a198af-cefe-734d-a995-89b9561344b6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_01a198af-cefe-799c-9be2-c7b13692a3c2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_01a198af-cefe-734d-a995-89b9561344b6" xlink:to="loc_srt_ProductOrServiceAxis_01a198af-cefe-799c-9be2-c7b13692a3c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cefe-799c-9be2-c7b13692a3c2_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cefe-799c-9be2-c7b13692a3c2" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cefe-799c-9be2-c7b13692a3c2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cefe-79dd-9bfc-2d2c78661c30" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cefe-799c-9be2-c7b13692a3c2" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cefe-79dd-9bfc-2d2c78661c30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CasinoMember_01a198af-cefe-7f78-b97a-3f424e146888" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CasinoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cefe-79dd-9bfc-2d2c78661c30" xlink:to="loc_us-gaap_CasinoMember_01a198af-cefe-7f78-b97a-3f424e146888" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OccupancyMember_01a198af-cefe-737f-84ea-c909d7bd4c44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OccupancyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cefe-79dd-9bfc-2d2c78661c30" xlink:to="loc_us-gaap_OccupancyMember_01a198af-cefe-737f-84ea-c909d7bd4c44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FoodAndBeverageMember_01a198af-cefe-77a9-a7ee-ec81e0c547c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FoodAndBeverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cefe-79dd-9bfc-2d2c78661c30" xlink:to="loc_us-gaap_FoodAndBeverageMember_01a198af-cefe-77a9-a7ee-ec81e0c547c9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EntertainmentRetailAndOtherMember_01a198af-cefe-7f09-b2f0-91da35d36b49" xlink:href="wynn-20260930.xsd#wynn_EntertainmentRetailAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cefe-79dd-9bfc-2d2c78661c30" xlink:to="loc_wynn_EntertainmentRetailAndOtherMember_01a198af-cefe-7f09-b2f0-91da35d36b49" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_01a198af-cefe-7eda-947d-40952d698994" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_RevenuesAbstract_01a198af-cefe-7eda-947d-40952d698994" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_01a198af-cefe-78d4-8543-404eb6ca52c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_01a198af-cefe-7eda-947d-40952d698994" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_01a198af-cefe-78d4-8543-404eb6ca52c7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_01a198af-cefe-77bd-b09c-67fca3027380" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_01a198af-cefe-77bd-b09c-67fca3027380" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_01a198af-cefe-718c-a8ab-1368a99557ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_01a198af-cefe-718c-a8ab-1368a99557ba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_01a198af-cefe-71d5-a480-095a41b36490" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForDoubtfulAccounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:to="loc_us-gaap_ProvisionForDoubtfulAccounts_01a198af-cefe-71d5-a480-095a41b36490" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreOpeningCosts_01a198af-cefe-7a46-a906-5e9d9ffbda63" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreOpeningCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:to="loc_us-gaap_PreOpeningCosts_01a198af-cefe-7a46-a906-5e9d9ffbda63" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_01a198af-cefe-73fa-ac2a-b4b4bec7b6de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:to="loc_us-gaap_DepreciationAndAmortization_01a198af-cefe-73fa-ac2a-b4b4bec7b6de" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_ProjectAbandonmentCosts_01a198af-cefe-76c1-99cc-35e403faa642" xlink:href="wynn-20260930.xsd#wynn_ProjectAbandonmentCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:to="loc_wynn_ProjectAbandonmentCosts_01a198af-cefe-76c1-99cc-35e403faa642" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpenses_01a198af-cefe-7d75-9203-d86dabf30941" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_01a198af-cefe-7ae1-8720-8156f484c0f2" xlink:to="loc_us-gaap_CostsAndExpenses_01a198af-cefe-7d75-9203-d86dabf30941" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_01a198af-cefe-74e0-af34-6010b98a6b3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_OperatingIncomeLoss_01a198af-cefe-74e0-af34-6010b98a6b3b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpenseAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInterest_01a198af-cefe-75af-a129-3b275ea1d79f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:to="loc_us-gaap_InvestmentIncomeInterest_01a198af-cefe-75af-a129-3b275ea1d79f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_01a198af-cefe-7912-b0e4-80c233fa8461" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:to="loc_us-gaap_InterestExpenseNonoperating_01a198af-cefe-7912-b0e4-80c233fa8461" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198af-cefe-727e-8fca-9e5bb8215d5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDerivativeInstrumentsNetPretax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:to="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198af-cefe-727e-8fca-9e5bb8215d5c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a198af-cefe-7949-a118-eaf7ca035756" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a198af-cefe-7949-a118-eaf7ca035756" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_01a198af-cefe-7c00-943f-86dc5a4e50f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_01a198af-cefe-7c00-943f-86dc5a4e50f2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_01a198af-cefe-71d5-bf1f-084cb88070c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cefe-7ecf-88aa-372ff596e936" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_01a198af-cefe-71d5-bf1f-084cb88070c6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_01a198af-cefe-7ef1-b87a-8de4c537d809" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_01a198af-cefe-7ef1-b87a-8de4c537d809" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_01a198af-cefe-7a8e-9c99-9942d0136488" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_01a198af-cefe-7a8e-9c99-9942d0136488" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_01a198af-cefe-7efa-b808-e5c2ef081844" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_ProfitLoss_01a198af-cefe-7efa-b808-e5c2ef081844" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_01a198af-cefe-78ad-9f9e-c97982551216" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_01a198af-cefe-78ad-9f9e-c97982551216" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_01a198af-cefe-7c7e-a39b-956d14ed2498" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_NetIncomeLoss_01a198af-cefe-7c7e-a39b-956d14ed2498" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EarningsPerShareBasicAndDilutedEPSAbstract_01a198af-cefe-7ca5-9b79-d8921a4ce318" xlink:href="wynn-20260930.xsd#wynn_EarningsPerShareBasicAndDilutedEPSAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_wynn_EarningsPerShareBasicAndDilutedEPSAbstract_01a198af-cefe-7ca5-9b79-d8921a4ce318" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareAbstract_01a198af-cefe-7752-bf9f-f6c6556dbf6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_EarningsPerShareBasicAndDilutedEPSAbstract_01a198af-cefe-7ca5-9b79-d8921a4ce318" xlink:to="loc_us-gaap_EarningsPerShareAbstract_01a198af-cefe-7752-bf9f-f6c6556dbf6d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_01a198af-cefe-7fa0-b4cb-7582a6a94972" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_01a198af-cefe-7752-bf9f-f6c6556dbf6d" xlink:to="loc_us-gaap_EarningsPerShareBasic_01a198af-cefe-7fa0-b4cb-7582a6a94972" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_01a198af-cefe-7e8c-821a-dc7f7fd77c52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_01a198af-cefe-7752-bf9f-f6c6556dbf6d" xlink:to="loc_us-gaap_EarningsPerShareDiluted_01a198af-cefe-7e8c-821a-dc7f7fd77c52" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_01a198af-cefe-7101-b7cc-3538ed5f1018" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-7c77-8f58-78d672b4aecd" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_01a198af-cefe-7101-b7cc-3538ed5f1018" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_01a198af-cefe-7c8a-9596-38ac491284f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_01a198af-cefe-7101-b7cc-3538ed5f1018" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_01a198af-cefe-7c8a-9596-38ac491284f2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_01a198af-cefe-71d9-89da-2706475a6698" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_01a198af-cefe-7101-b7cc-3538ed5f1018" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_01a198af-cefe-71d9-89da-2706475a6698" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/CondensedConsolidatedStatementofStockholdersDeficitunaudited" xlink:type="simple" xlink:href="wynn-20260930.xsd#CondensedConsolidatedStatementofStockholdersDeficitunaudited"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/CondensedConsolidatedStatementofStockholdersDeficitunaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_01a198af-cefe-71de-af2c-5cc22fc598b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_01a198af-cefe-702d-ade8-9badbaf47463" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-71de-af2c-5cc22fc598b2" xlink:to="loc_us-gaap_StatementTable_01a198af-cefe-702d-ade8-9badbaf47463" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_01a198af-cefe-77e4-aecf-5d7fa8942607" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_01a198af-cefe-702d-ade8-9badbaf47463" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_01a198af-cefe-77e4-aecf-5d7fa8942607" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a198af-cefe-77e4-aecf-5d7fa8942607_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a198af-cefe-77e4-aecf-5d7fa8942607" xlink:to="loc_us-gaap_EquityComponentDomain_01a198af-cefe-77e4-aecf-5d7fa8942607_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a198af-cefe-7c98-9b02-cdaeb90c958e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_01a198af-cefe-77e4-aecf-5d7fa8942607" xlink:to="loc_us-gaap_EquityComponentDomain_01a198af-cefe-7c98-9b02-cdaeb90c958e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ParentMember_01a198af-cefe-7b49-8dce-a001f8173ffb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a198af-cefe-7c98-9b02-cdaeb90c958e" xlink:to="loc_us-gaap_ParentMember_01a198af-cefe-7b49-8dce-a001f8173ffb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_01a198af-cefe-76c4-9866-2b19f14c314b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_01a198af-cefe-7b49-8dce-a001f8173ffb" xlink:to="loc_us-gaap_CommonStockMember_01a198af-cefe-76c4-9866-2b19f14c314b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_01a198af-cefe-78e5-8fa1-033a064dab11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_01a198af-cefe-7b49-8dce-a001f8173ffb" xlink:to="loc_us-gaap_TreasuryStockCommonMember_01a198af-cefe-78e5-8fa1-033a064dab11" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_01a198af-cefe-7817-8014-79751c3910a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_01a198af-cefe-7b49-8dce-a001f8173ffb" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_01a198af-cefe-7817-8014-79751c3910a4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a198af-cefe-7520-b721-5d4b9e094f0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_01a198af-cefe-7b49-8dce-a001f8173ffb" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_01a198af-cefe-7520-b721-5d4b9e094f0d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_01a198af-cefe-794a-9694-15c5c740cc00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_01a198af-cefe-7b49-8dce-a001f8173ffb" xlink:to="loc_us-gaap_RetainedEarningsMember_01a198af-cefe-794a-9694-15c5c740cc00" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestMember_01a198af-cefe-7ef0-b8a4-c66e5e1ef3ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_01a198af-cefe-7c98-9b02-cdaeb90c958e" xlink:to="loc_us-gaap_NoncontrollingInterestMember_01a198af-cefe-7ef0-b8a4-c66e5e1ef3ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_01a198af-cefe-71de-af2c-5cc22fc598b2" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_01a198af-cefe-730b-947d-4ac771591230" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_SharesOutstanding_01a198af-cefe-730b-947d-4ac771591230" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a198af-cefe-751e-bfed-7dd7bd9a6441" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a198af-cefe-751e-bfed-7dd7bd9a6441" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_01a198af-cefe-7be7-916e-8e092d6548db" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_ProfitLoss_01a198af-cefe-7be7-916e-8e092d6548db" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_01a198af-cefe-7539-a3a0-fd973b2e1578" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_01a198af-cefe-7539-a3a0-fd973b2e1578" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_01a198af-cefe-7c67-9e10-fc19c5ad620e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_01a198af-cefe-7c67-9e10-fc19c5ad620e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_01a198af-cefe-7466-8765-8861eb5af5b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_01a198af-cefe-7466-8765-8861eb5af5b0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_01a198af-cefe-7f10-888b-834dbd026195" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_01a198af-cefe-7f10-888b-834dbd026195" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_01a198af-cefe-7df9-a217-cf07616d9765" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_01a198af-cefe-7df9-a217-cf07616d9765" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited_01a198af-cefe-730c-a6ce-ccba1b0291ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited_01a198af-cefe-730c-a6ce-ccba1b0291ee" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_01a198af-cefe-7759-9066-6091f775c673" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_01a198af-cefe-7759-9066-6091f775c673" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a198af-cefe-774b-b5a7-b6c057e0ba13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a198af-cefe-774b-b5a7-b6c057e0ba13" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockCash_01a198af-cefe-76db-a37a-7cd58fec3d8c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStockCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_DividendsCommonStockCash_01a198af-cefe-76db-a37a-7cd58fec3d8c" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_01a198af-cefe-7691-8b7b-5cda55addaee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_01a198af-cefe-7691-8b7b-5cda55addaee" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_NoncontrollingInterestTransactionsWithSubsidiaryMinorityShareholdersValue_01a198af-cefe-7a41-8abe-ac6196eebc08" xlink:href="wynn-20260930.xsd#wynn_NoncontrollingInterestTransactionsWithSubsidiaryMinorityShareholdersValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_wynn_NoncontrollingInterestTransactionsWithSubsidiaryMinorityShareholdersValue_01a198af-cefe-7a41-8abe-ac6196eebc08" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_01a198af-cefe-7def-b1aa-d13bcb143783" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a198af-cefe-74f1-9a37-b16ab54620be" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_01a198af-cefe-7def-b1aa-d13bcb143783" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_01a198af-cefe-7234-a136-162c9b5cfed1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_01a198af-cefe-70fe-bc33-4f7d064e06e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/OrganizationDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#OrganizationDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/OrganizationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-7a0c-a5b6-059e163dab5c" xlink:href="wynn-20260930.xsd#wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable_01a198af-cfbc-77af-9611-3b4f4e80252b" xlink:href="wynn-20260930.xsd#wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-7a0c-a5b6-059e163dab5c" xlink:to="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable_01a198af-cfbc-77af-9611-3b4f4e80252b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_01a198af-cfbc-71b2-8b3e-f55fd6b615ff" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable_01a198af-cfbc-77af-9611-3b4f4e80252b" xlink:to="loc_srt_OwnershipAxis_01a198af-cfbc-71b2-8b3e-f55fd6b615ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-71b2-8b3e-f55fd6b615ff_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-71b2-8b3e-f55fd6b615ff" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-71b2-8b3e-f55fd6b615ff_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-712d-aeb1-8e8ff8df73fc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-71b2-8b3e-f55fd6b615ff" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-712d-aeb1-8e8ff8df73fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnPalaceandWynnMacauMember_01a198af-cfbc-7ccb-a53d-0e84262c1ed7" xlink:href="wynn-20260930.xsd#wynn_WynnPalaceandWynnMacauMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_01a198af-cfbc-712d-aeb1-8e8ff8df73fc" xlink:to="loc_wynn_WynnPalaceandWynnMacauMember_01a198af-cfbc-7ccb-a53d-0e84262c1ed7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnLasVegasMember_01a198af-cfbc-738e-be85-bf42da04a7d4" xlink:href="wynn-20260930.xsd#wynn_WynnLasVegasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_01a198af-cfbc-712d-aeb1-8e8ff8df73fc" xlink:to="loc_wynn_WynnLasVegasMember_01a198af-cfbc-738e-be85-bf42da04a7d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_RetailJointVentureMember_01a198af-cfbc-7eac-9a61-bcd80402b1c2" xlink:href="wynn-20260930.xsd#wynn_RetailJointVentureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_01a198af-cfbc-712d-aeb1-8e8ff8df73fc" xlink:to="loc_wynn_RetailJointVentureMember_01a198af-cfbc-7eac-9a61-bcd80402b1c2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-7750-afd7-db25a5222718" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable_01a198af-cfbc-77af-9611-3b4f4e80252b" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-7750-afd7-db25a5222718" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7750-afd7-db25a5222718_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-7750-afd7-db25a5222718" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7750-afd7-db25a5222718_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-77ca-aa34-7989ea6e4471" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-7750-afd7-db25a5222718" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-77ca-aa34-7989ea6e4471" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_Island3AMIFZLLCMember_01a198af-cfbc-7ea3-8c80-463003a6065c" xlink:href="wynn-20260930.xsd#wynn_Island3AMIFZLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-77ca-aa34-7989ea6e4471" xlink:to="loc_wynn_Island3AMIFZLLCMember_01a198af-cfbc-7ea3-8c80-463003a6065c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestOwnershipPercentageByParent_01a198af-cfbc-70c2-926d-b8b86b0d8542" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestOwnershipPercentageByParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-7a0c-a5b6-059e163dab5c" xlink:to="loc_us-gaap_MinorityInterestOwnershipPercentageByParent_01a198af-cfbc-70c2-926d-b8b86b0d8542" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_01a198af-cfbc-77ee-ac6d-4d3f65231554" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-7a0c-a5b6-059e163dab5c" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_01a198af-cfbc-77ee-ac6d-4d3f65231554" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/BasisofPresentationandSignificantAccountingPoliciesDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#BasisofPresentationandSignificantAccountingPoliciesDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/BasisofPresentationandSignificantAccountingPoliciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:href="wynn-20260930.xsd#wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable_01a198af-cfbc-7f7d-8312-01b260f7ee14" xlink:href="wynn-20260930.xsd#wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:to="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable_01a198af-cfbc-7f7d-8312-01b260f7ee14" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_01a198af-cfbc-7e5e-ab85-6f4b7e9b6f92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTable_01a198af-cfbc-7f7d-8312-01b260f7ee14" xlink:to="loc_us-gaap_FinancialInstrumentAxis_01a198af-cfbc-7e5e-ab85-6f4b7e9b6f92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a198af-cfbc-7e5e-ab85-6f4b7e9b6f92_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a198af-cfbc-7e5e-ab85-6f4b7e9b6f92" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a198af-cfbc-7e5e-ab85-6f4b7e9b6f92_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a198af-cfbc-77b9-a252-de4e57cedabe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a198af-cfbc-7e5e-ab85-6f4b7e9b6f92" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a198af-cfbc-77b9-a252-de4e57cedabe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FixedIncomeInvestmentsMember_01a198af-cfbc-7aef-baaa-6d725ea72c56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FixedIncomeInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a198af-cfbc-77b9-a252-de4e57cedabe" xlink:to="loc_us-gaap_FixedIncomeInvestmentsMember_01a198af-cfbc-7aef-baaa-6d725ea72c56" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_01a198af-cfbc-7e4a-ba1f-aea966dfdf5e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a198af-cfbc-77b9-a252-de4e57cedabe" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_01a198af-cfbc-7e4a-ba1f-aea966dfdf5e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_GamingTaxExpenses_01a198af-cfbc-7ea2-823f-1bad7e45ce62" xlink:href="wynn-20260930.xsd#wynn_GamingTaxExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:to="loc_wynn_GamingTaxExpenses_01a198af-cfbc-7ea2-823f-1bad7e45ce62" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_01a198af-cfbc-78b6-b5b0-48566cbeae5a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_01a198af-cfbc-78b6-b5b0-48566cbeae5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Investments_01a198af-cfbc-7c0c-87d6-4371bcda7e63" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Investments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:to="loc_us-gaap_Investments_01a198af-cfbc-7c0c-87d6-4371bcda7e63" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermInvestments_01a198af-cfbc-74cf-8e01-9605ced31146" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:to="loc_us-gaap_LongTermInvestments_01a198af-cfbc-74cf-8e01-9605ced31146" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss_01a198af-cfbc-76f8-a45b-5209d1d70bd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss_01a198af-cfbc-76f8-a45b-5209d1d70bd1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a198af-cfbc-7746-8aa8-aa0ef7858429" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureLineItems_01a198af-cfbc-79ae-b846-85ce02a1848f" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a198af-cfbc-7746-8aa8-aa0ef7858429" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/ReceivablesnetDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#ReceivablesnetDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/ReceivablesnetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_01a198af-cfbc-7522-922c-162dcf050f17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_01a198af-cfbc-7068-889b-52acb4d60d89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_01a198af-cfbc-7522-922c-162dcf050f17" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_01a198af-cfbc-7068-889b-52acb4d60d89" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis_01a198af-cfbc-7874-91b7-722f6b25b127" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_01a198af-cfbc-7068-889b-52acb4d60d89" xlink:to="loc_us-gaap_AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis_01a198af-cfbc-7874-91b7-722f6b25b127" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LegalEntityTypeOfCounterpartyDomain_01a198af-cfbc-7874-91b7-722f6b25b127_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LegalEntityTypeOfCounterpartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis_01a198af-cfbc-7874-91b7-722f6b25b127" xlink:to="loc_us-gaap_LegalEntityTypeOfCounterpartyDomain_01a198af-cfbc-7874-91b7-722f6b25b127_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LegalEntityTypeOfCounterpartyDomain_01a198af-cfbc-7920-8683-7b7b86c594df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LegalEntityTypeOfCounterpartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis_01a198af-cfbc-7874-91b7-722f6b25b127" xlink:to="loc_us-gaap_LegalEntityTypeOfCounterpartyDomain_01a198af-cfbc-7920-8683-7b7b86c594df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CasinoMember_01a198af-cfbc-7598-b2f5-ec0ec88f006d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CasinoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LegalEntityTypeOfCounterpartyDomain_01a198af-cfbc-7920-8683-7b7b86c594df" xlink:to="loc_us-gaap_CasinoMember_01a198af-cfbc-7598-b2f5-ec0ec88f006d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_01a198af-cfbc-7a0d-af01-9f0423a1a588" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LegalEntityTypeOfCounterpartyDomain_01a198af-cfbc-7920-8683-7b7b86c594df" xlink:to="loc_srt_HotelMember_01a198af-cfbc-7a0d-af01-9f0423a1a588" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_RetailLeasesAndOtherMember_01a198af-cfbc-72cc-9a4d-cd4709412e17" xlink:href="wynn-20260930.xsd#wynn_RetailLeasesAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LegalEntityTypeOfCounterpartyDomain_01a198af-cfbc-7920-8683-7b7b86c594df" xlink:to="loc_wynn_RetailLeasesAndOtherMember_01a198af-cfbc-72cc-9a4d-cd4709412e17" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_01a198af-cfbc-7635-a2d6-b9bde3186887" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_01a198af-cfbc-7068-889b-52acb4d60d89" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_01a198af-cfbc-7635-a2d6-b9bde3186887" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_01a198af-cfbc-7635-a2d6-b9bde3186887_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_01a198af-cfbc-7635-a2d6-b9bde3186887" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_01a198af-cfbc-7635-a2d6-b9bde3186887_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_01a198af-cfbc-77f7-8caa-fddabffd03b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_01a198af-cfbc-7635-a2d6-b9bde3186887" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_01a198af-cfbc-77f7-8caa-fddabffd03b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicConcentrationRiskMember_01a198af-cfbc-7821-b271-f83092aff5fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_01a198af-cfbc-77f7-8caa-fddabffd03b6" xlink:to="loc_us-gaap_GeographicConcentrationRiskMember_01a198af-cfbc-7821-b271-f83092aff5fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_01a198af-cfbc-77c4-9aac-f000edebbc31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_01a198af-cfbc-7068-889b-52acb4d60d89" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_01a198af-cfbc-77c4-9aac-f000edebbc31" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a198af-cfbc-77c4-9aac-f000edebbc31_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_01a198af-cfbc-77c4-9aac-f000edebbc31" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a198af-cfbc-77c4-9aac-f000edebbc31_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a198af-cfbc-7b32-b024-ee41688274db" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_01a198af-cfbc-77c4-9aac-f000edebbc31" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a198af-cfbc-7b32-b024-ee41688274db" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableMember_01a198af-cfbc-70fd-9f96-6ab2c4b1d20b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a198af-cfbc-7b32-b024-ee41688274db" xlink:to="loc_us-gaap_AccountsReceivableMember_01a198af-cfbc-70fd-9f96-6ab2c4b1d20b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7a25-811b-8f8f6948fe9c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_01a198af-cfbc-7068-889b-52acb4d60d89" xlink:to="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7a25-811b-8f8f6948fe9c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-7a25-811b-8f8f6948fe9c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7a25-811b-8f8f6948fe9c" xlink:to="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-7a25-811b-8f8f6948fe9c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-709c-ab60-4cfacb0d40f2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7a25-811b-8f8f6948fe9c" xlink:to="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-709c-ab60-4cfacb0d40f2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaMember_01a198af-cfbc-7521-89f4-1dffc19805c0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AsiaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-709c-ab60-4cfacb0d40f2" xlink:to="loc_srt_AsiaMember_01a198af-cfbc-7521-89f4-1dffc19805c0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableGrossCurrent_01a198af-cfbc-79f0-af9d-04118efbb351" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableGrossCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_01a198af-cfbc-7522-922c-162dcf050f17" xlink:to="loc_us-gaap_AccountsReceivableGrossCurrent_01a198af-cfbc-79f0-af9d-04118efbb351" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_01a198af-cfbc-7b14-a970-49530dcc39d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_01a198af-cfbc-7522-922c-162dcf050f17" xlink:to="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_01a198af-cfbc-7b14-a970-49530dcc39d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivablesNetCurrent_01a198af-cfbc-73d0-a816-7b27bd7763c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReceivablesNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_01a198af-cfbc-7522-922c-162dcf050f17" xlink:to="loc_us-gaap_ReceivablesNetCurrent_01a198af-cfbc-73d0-a816-7b27bd7763c3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_01a198af-cfbc-70c1-96f8-e9c072dd5529" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_01a198af-cfbc-7522-922c-162dcf050f17" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_01a198af-cfbc-70c1-96f8-e9c072dd5529" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_AccountsReceivableAllowanceForCreditLossPercentOfGrossCasinoReceivables_01a198af-cfbc-7c80-9916-04bd326e7780" xlink:href="wynn-20260930.xsd#wynn_AccountsReceivableAllowanceForCreditLossPercentOfGrossCasinoReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_01a198af-cfbc-7522-922c-162dcf050f17" xlink:to="loc_wynn_AccountsReceivableAllowanceForCreditLossPercentOfGrossCasinoReceivables_01a198af-cfbc-7c80-9916-04bd326e7780" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/LongTermDebtSummaryofLongTermDebtDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#LongTermDebtSummaryofLongTermDebtDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/LongTermDebtSummaryofLongTermDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-71de-bf7c-f5a441d34a28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-71de-bf7c-f5a441d34a28" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-76c5-8a73-0861f42aad96" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-71de-bf7c-f5a441d34a28" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-76c5-8a73-0861f42aad96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-76c5-8a73-0861f42aad96_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-76c5-8a73-0861f42aad96" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-76c5-8a73-0861f42aad96_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-719a-bd22-6de3fff66c8b" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-76c5-8a73-0861f42aad96" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-719a-bd22-6de3fff66c8b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WMCaymanHoldingsLimitedIIMember_01a198af-cfbc-7f38-a203-2cb7a6b7e9b1" xlink:href="wynn-20260930.xsd#wynn_WMCaymanHoldingsLimitedIIMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-719a-bd22-6de3fff66c8b" xlink:to="loc_wynn_WMCaymanHoldingsLimitedIIMember_01a198af-cfbc-7f38-a203-2cb7a6b7e9b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-72dc-a0f7-b46070298439" xlink:href="wynn-20260930.xsd#wynn_WynnMacauLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-719a-bd22-6de3fff66c8b" xlink:to="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-72dc-a0f7-b46070298439" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnResortsFinanceLLCMember_01a198af-cfbc-7901-82bd-8cc798ecd96d" xlink:href="wynn-20260930.xsd#wynn_WynnResortsFinanceLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-719a-bd22-6de3fff66c8b" xlink:to="loc_wynn_WynnResortsFinanceLLCMember_01a198af-cfbc-7901-82bd-8cc798ecd96d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnLasVegasLLCandWynnLasVegasCapitalCorpMember_01a198af-cfbc-7ac1-82fb-ad2c301ed17f" xlink:href="wynn-20260930.xsd#wynn_WynnLasVegasLLCandWynnLasVegasCapitalCorpMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-719a-bd22-6de3fff66c8b" xlink:to="loc_wynn_WynnLasVegasLLCandWynnLasVegasCapitalCorpMember_01a198af-cfbc-7ac1-82fb-ad2c301ed17f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnCAPlazaPropertyOwnerLLCAndWynnCAPropertyOwnerLLCMember_01a198af-cfbc-70e8-923d-7fa3e3dbca98" xlink:href="wynn-20260930.xsd#wynn_WynnCAPlazaPropertyOwnerLLCAndWynnCAPropertyOwnerLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-719a-bd22-6de3fff66c8b" xlink:to="loc_wynn_WynnCAPlazaPropertyOwnerLLCAndWynnCAPropertyOwnerLLCMember_01a198af-cfbc-70e8-923d-7fa3e3dbca98" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-750e-83f0-c72ca44d910a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-71de-bf7c-f5a441d34a28" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-750e-83f0-c72ca44d910a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-750e-83f0-c72ca44d910a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-750e-83f0-c72ca44d910a" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-750e-83f0-c72ca44d910a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-750e-83f0-c72ca44d910a" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WMCaymanIIRevolverDue2025Member_01a198af-cfbc-72f7-bfbc-1c1027b482b7" xlink:href="wynn-20260930.xsd#wynn_WMCaymanIIRevolverDue2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_WMCaymanIIRevolverDue2025Member_01a198af-cfbc-72f7-bfbc-1c1027b482b7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FiveAndOneOverTwoPercentageWynnMacauLimitedSeniorNotesDueOctoberOneTwoThousandTwentySevenMember_01a198af-cfbc-76a0-8b9b-d2c08abee3c8" xlink:href="wynn-20260930.xsd#wynn_FiveAndOneOverTwoPercentageWynnMacauLimitedSeniorNotesDueOctoberOneTwoThousandTwentySevenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_FiveAndOneOverTwoPercentageWynnMacauLimitedSeniorNotesDueOctoberOneTwoThousandTwentySevenMember_01a198af-cfbc-76a0-8b9b-d2c08abee3c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FiveAndOneOverEightPercentageWynnMacauLimitedSeniorNotesDueTwoThousandTwentyNineMember_01a198af-cfbc-7bf5-aca4-f883c391c71c" xlink:href="wynn-20260930.xsd#wynn_FiveAndOneOverEightPercentageWynnMacauLimitedSeniorNotesDueTwoThousandTwentyNineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_FiveAndOneOverEightPercentageWynnMacauLimitedSeniorNotesDueTwoThousandTwentyNineMember_01a198af-cfbc-7bf5-aca4-f883c391c71c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FiveAndFiveOverEightPercentageWynnMacauLimitedSeniorNotesDueTwoThousandTwentyEightMember_01a198af-cfbc-7ae6-8ed6-e21cc08ed387" xlink:href="wynn-20260930.xsd#wynn_FiveAndFiveOverEightPercentageWynnMacauLimitedSeniorNotesDueTwoThousandTwentyEightMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_FiveAndFiveOverEightPercentageWynnMacauLimitedSeniorNotesDueTwoThousandTwentyEightMember_01a198af-cfbc-7ae6-8ed6-e21cc08ed387" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_SixAndThreeOverFourPercentageWynnMacauLimitedSeniorNotesDueTwoThousandThirtyFourMember_01a198af-cfbc-7b55-8963-edbb1a20c7ed" xlink:href="wynn-20260930.xsd#wynn_SixAndThreeOverFourPercentageWynnMacauLimitedSeniorNotesDueTwoThousandThirtyFourMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_SixAndThreeOverFourPercentageWynnMacauLimitedSeniorNotesDueTwoThousandThirtyFourMember_01a198af-cfbc-7b55-8963-edbb1a20c7ed" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FourAndOneOverTwoPercentageWynnMacauLimitedConvertibleBondsDueTwoThousandTwentyNineMember_01a198af-cfbc-7b00-8853-78773040b2c5" xlink:href="wynn-20260930.xsd#wynn_FourAndOneOverTwoPercentageWynnMacauLimitedConvertibleBondsDueTwoThousandTwentyNineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_FourAndOneOverTwoPercentageWynnMacauLimitedConvertibleBondsDueTwoThousandTwentyNineMember_01a198af-cfbc-7b00-8853-78773040b2c5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WRFSeniorSecuredCreditFacilitiesMember_01a198af-cfbc-75ab-994d-9932b31b6612" xlink:href="wynn-20260930.xsd#wynn_WRFSeniorSecuredCreditFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_WRFSeniorSecuredCreditFacilitiesMember_01a198af-cfbc-75ab-994d-9932b31b6612" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_SeniorTermLoanFacilityDue2030Member_01a198af-cfbc-7cc3-b02e-6fee469f97b2" xlink:href="wynn-20260930.xsd#wynn_SeniorTermLoanFacilityDue2030Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_WRFSeniorSecuredCreditFacilitiesMember_01a198af-cfbc-75ab-994d-9932b31b6612" xlink:to="loc_wynn_SeniorTermLoanFacilityDue2030Member_01a198af-cfbc-7cc3-b02e-6fee469f97b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WRFRevolverDue2030Member_01a198af-cfbc-790f-bfae-b30b5d5bfd8d" xlink:href="wynn-20260930.xsd#wynn_WRFRevolverDue2030Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_WRFSeniorSecuredCreditFacilitiesMember_01a198af-cfbc-75ab-994d-9932b31b6612" xlink:to="loc_wynn_WRFRevolverDue2030Member_01a198af-cfbc-790f-bfae-b30b5d5bfd8d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FiveAndOneOverFourPercentageSeniorNotesDueMay152027Member_01a198af-cfbc-7c47-ad01-3dfcf50c853c" xlink:href="wynn-20260930.xsd#wynn_FiveAndOneOverFourPercentageSeniorNotesDueMay152027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_FiveAndOneOverFourPercentageSeniorNotesDueMay152027Member_01a198af-cfbc-7c47-ad01-3dfcf50c853c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FiveAndOneOverEightPercentageSeniorNotesDue2029Member_01a198af-cfbc-7057-b420-55bd407833d7" xlink:href="wynn-20260930.xsd#wynn_FiveAndOneOverEightPercentageSeniorNotesDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_FiveAndOneOverEightPercentageSeniorNotesDue2029Member_01a198af-cfbc-7057-b420-55bd407833d7" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_SevenAndOneOverEightPercentageSeniorNotesDue2031Member_01a198af-cfbc-7746-849a-79d268d7aa14" xlink:href="wynn-20260930.xsd#wynn_SevenAndOneOverEightPercentageSeniorNotesDue2031Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_SevenAndOneOverEightPercentageSeniorNotesDue2031Member_01a198af-cfbc-7746-849a-79d268d7aa14" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_A614SeniorNotesDue2033Member_01a198af-cfbc-7b68-b8f9-b602048e10d1" xlink:href="wynn-20260930.xsd#wynn_A614SeniorNotesDue2033Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_A614SeniorNotesDue2033Member_01a198af-cfbc-7b68-b8f9-b602048e10d1" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_A678SeniorNotesDue2035Member_01a198e0-836e-799a-aafa-ddac6db9c73c" xlink:href="wynn-20260930.xsd#wynn_A678SeniorNotesDue2035Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_A678SeniorNotesDue2035Member_01a198e0-836e-799a-aafa-ddac6db9c73c" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_RetailTermLoanAgreementMember_01a198af-cfbc-7b93-808d-2001d53302d0" xlink:href="wynn-20260930.xsd#wynn_RetailTermLoanAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a43-8ae6-bcd91543b705" xlink:to="loc_wynn_RetailTermLoanAgreementMember_01a198af-cfbc-7b93-808d-2001d53302d0" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7898-ad1f-1dba499eb413" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-71de-bf7c-f5a441d34a28" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7898-ad1f-1dba499eb413" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7898-ad1f-1dba499eb413_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7898-ad1f-1dba499eb413" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7898-ad1f-1dba499eb413_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-764a-b651-a2f11e369ae7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7898-ad1f-1dba499eb413" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-764a-b651-a2f11e369ae7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_01a198af-cfbc-7700-8724-17c07d2f4a09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-764a-b651-a2f11e369ae7" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_01a198af-cfbc-7700-8724-17c07d2f4a09" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_01a198af-cfbc-7566-9544-9d39f1a04b39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-764a-b651-a2f11e369ae7" xlink:to="loc_us-gaap_SeniorNotesMember_01a198af-cfbc-7566-9544-9d39f1a04b39" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtMember_01a198af-cfbc-7f49-a24d-6b511fe98197" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-764a-b651-a2f11e369ae7" xlink:to="loc_us-gaap_ConvertibleDebtMember_01a198af-cfbc-7f49-a24d-6b511fe98197" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_01a198af-cfbc-723a-842e-ed5173ebba29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-764a-b651-a2f11e369ae7" xlink:to="loc_us-gaap_SecuredDebtMember_01a198af-cfbc-723a-842e-ed5173ebba29" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_01a198af-cfbc-7f8f-972e-b2e228ed9cab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-764a-b651-a2f11e369ae7" xlink:to="loc_us-gaap_MediumTermNotesMember_01a198af-cfbc-7f8f-972e-b2e228ed9cab" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_01a198af-cfbc-728f-9096-2c990704442e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_01a198af-cfbc-728f-9096-2c990704442e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_01a198af-cfbc-758c-a74d-6cf8febee4ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_DerivativeLiabilities_01a198af-cfbc-758c-a74d-6cf8febee4ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_01a198af-cfbc-78f1-8651-310449fd2cf2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_01a198af-cfbc-78f1-8651-310449fd2cf2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_01a198af-cfbc-7f69-8800-d78181e6396d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_LongTermDebt_01a198af-cfbc-7f69-8800-d78181e6396d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_01a198af-cfbc-7c84-8740-531327a966ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_LongTermDebtCurrent_01a198af-cfbc-7c84-8740-531327a966ca" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_01a198af-cfbc-7402-9bb8-40399a080968" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_01a198af-cfbc-7402-9bb8-40399a080968" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a198af-cfbc-7498-a644-67bb15f7eec8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7155-afe7-3e8219f85f21" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a198af-cfbc-7498-a644-67bb15f7eec8" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/LongTermDebtSummaryofLongTermDebtAdditionalInformationDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#LongTermDebtSummaryofLongTermDebtAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/LongTermDebtSummaryofLongTermDebtAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-7bcf-a098-410dd03fae36" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-7bcf-a098-410dd03fae36" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_01a198af-cfbc-7a30-b5bd-0dd641e8a81e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-7bcf-a098-410dd03fae36" xlink:to="loc_us-gaap_VariableRateAxis_01a198af-cfbc-7a30-b5bd-0dd641e8a81e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7a30-b5bd-0dd641e8a81e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_01a198af-cfbc-7a30-b5bd-0dd641e8a81e" xlink:to="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7a30-b5bd-0dd641e8a81e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7e58-b90e-42098f376708" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_01a198af-cfbc-7a30-b5bd-0dd641e8a81e" xlink:to="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7e58-b90e-42098f376708" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrMember_01a198af-cfbc-792c-b8bb-c3e64f6fb505" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredOvernightFinancingRateSofrMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7e58-b90e-42098f376708" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrMember_01a198af-cfbc-792c-b8bb-c3e64f6fb505" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_HIBOROrLIBORMember_01a198af-cfbc-760b-a4aa-b4bcad6195cd" xlink:href="wynn-20260930.xsd#wynn_HIBOROrLIBORMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7e58-b90e-42098f376708" xlink:to="loc_wynn_HIBOROrLIBORMember_01a198af-cfbc-760b-a4aa-b4bcad6195cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_LondonInterbankOfferedRateLIBOR1Member_01a198af-cfbc-7d34-a992-a7642515a510" xlink:href="wynn-20260930.xsd#wynn_LondonInterbankOfferedRateLIBOR1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7e58-b90e-42098f376708" xlink:to="loc_wynn_LondonInterbankOfferedRateLIBOR1Member_01a198af-cfbc-7d34-a992-a7642515a510" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_HIBORMember_01a198af-cfbc-7d8e-8f88-7424377ddee1" xlink:href="wynn-20260930.xsd#wynn_HIBORMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198af-cfbc-7e58-b90e-42098f376708" xlink:to="loc_wynn_HIBORMember_01a198af-cfbc-7d8e-8f88-7424377ddee1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-7d76-b000-d35ac0ac34cd" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-7bcf-a098-410dd03fae36" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-7d76-b000-d35ac0ac34cd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-7d76-b000-d35ac0ac34cd_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7d76-b000-d35ac0ac34cd" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-7d76-b000-d35ac0ac34cd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-70fd-9a65-44d2bfd9ffea" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7d76-b000-d35ac0ac34cd" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-70fd-9a65-44d2bfd9ffea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WMCaymanHoldingsLimitedIIMember_01a198af-cfbc-7a6d-b771-5d3db8296f7e" xlink:href="wynn-20260930.xsd#wynn_WMCaymanHoldingsLimitedIIMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-70fd-9a65-44d2bfd9ffea" xlink:to="loc_wynn_WMCaymanHoldingsLimitedIIMember_01a198af-cfbc-7a6d-b771-5d3db8296f7e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-7ef4-8748-9ef6383385fd" xlink:href="wynn-20260930.xsd#wynn_WynnMacauLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-70fd-9a65-44d2bfd9ffea" xlink:to="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-7ef4-8748-9ef6383385fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnResortsFinanceLLCMember_01a198af-cfbc-77a2-a3a3-2e92d5c2f434" xlink:href="wynn-20260930.xsd#wynn_WynnResortsFinanceLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-70fd-9a65-44d2bfd9ffea" xlink:to="loc_wynn_WynnResortsFinanceLLCMember_01a198af-cfbc-77a2-a3a3-2e92d5c2f434" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnCAPlazaPropertyOwnerLLCAndWynnCAPropertyOwnerLLCMember_01a198af-cfbc-7094-9cd2-be6026b038b1" xlink:href="wynn-20260930.xsd#wynn_WynnCAPlazaPropertyOwnerLLCAndWynnCAPropertyOwnerLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-70fd-9a65-44d2bfd9ffea" xlink:to="loc_wynn_WynnCAPlazaPropertyOwnerLLCAndWynnCAPropertyOwnerLLCMember_01a198af-cfbc-7094-9cd2-be6026b038b1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7a95-bea6-82f628520da4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-7bcf-a098-410dd03fae36" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7a95-bea6-82f628520da4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a95-bea6-82f628520da4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7a95-bea6-82f628520da4" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7a95-bea6-82f628520da4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7a95-bea6-82f628520da4" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WMCaymanIIRevolverDue2025Member_01a198af-cfbc-7f6b-baa2-94f1a0eb395c" xlink:href="wynn-20260930.xsd#wynn_WMCaymanIIRevolverDue2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:to="loc_wynn_WMCaymanIIRevolverDue2025Member_01a198af-cfbc-7f6b-baa2-94f1a0eb395c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FourAndOneOverTwoPercentageWynnMacauLimitedConvertibleBondsDueTwoThousandTwentyNineMember_01a198af-cfbc-7f56-a1a8-0e00cf8d00cb" xlink:href="wynn-20260930.xsd#wynn_FourAndOneOverTwoPercentageWynnMacauLimitedConvertibleBondsDueTwoThousandTwentyNineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:to="loc_wynn_FourAndOneOverTwoPercentageWynnMacauLimitedConvertibleBondsDueTwoThousandTwentyNineMember_01a198af-cfbc-7f56-a1a8-0e00cf8d00cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WRFSeniorSecuredCreditFacilitiesMember_01a198af-cfbc-76f5-aa16-5c751dc9be8f" xlink:href="wynn-20260930.xsd#wynn_WRFSeniorSecuredCreditFacilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:to="loc_wynn_WRFSeniorSecuredCreditFacilitiesMember_01a198af-cfbc-76f5-aa16-5c751dc9be8f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_RetailTermLoanAgreementMember_01a198af-cfbc-7d3c-a750-649d72d222c1" xlink:href="wynn-20260930.xsd#wynn_RetailTermLoanAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:to="loc_wynn_RetailTermLoanAgreementMember_01a198af-cfbc-7d3c-a750-649d72d222c1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_SeniorTermLoanFacilityDue2030Member_01a198f3-c9da-78b6-9806-47a64396b31f" xlink:href="wynn-20260930.xsd#wynn_SeniorTermLoanFacilityDue2030Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:to="loc_wynn_SeniorTermLoanFacilityDue2030Member_01a198f3-c9da-78b6-9806-47a64396b31f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WRFRevolverDue2030Member_01a198f3-c9da-7faa-9440-0568c27534ab" xlink:href="wynn-20260930.xsd#wynn_WRFRevolverDue2030Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-718f-b761-637f34f218ef" xlink:to="loc_wynn_WRFRevolverDue2030Member_01a198f3-c9da-7faa-9440-0568c27534ab" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7519-8be3-72bacc5ba7cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-7bcf-a098-410dd03fae36" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7519-8be3-72bacc5ba7cc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7519-8be3-72bacc5ba7cc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7519-8be3-72bacc5ba7cc" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7519-8be3-72bacc5ba7cc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-72ac-ac47-500fd81613cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7519-8be3-72bacc5ba7cc" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-72ac-ac47-500fd81613cf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_01a198af-cfbc-7f3b-bc89-e8007ee4516d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-72ac-ac47-500fd81613cf" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_01a198af-cfbc-7f3b-bc89-e8007ee4516d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtMember_01a198af-cfbc-7016-a11e-e9ede0754c71" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-72ac-ac47-500fd81613cf" xlink:to="loc_us-gaap_ConvertibleDebtMember_01a198af-cfbc-7016-a11e-e9ede0754c71" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_01a198af-cfbc-7405-8106-06543918d954" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-72ac-ac47-500fd81613cf" xlink:to="loc_us-gaap_SecuredDebtMember_01a198af-cfbc-7405-8106-06543918d954" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MediumTermNotesMember_01a198af-cfbc-7d62-b2bb-cdea67e1a107" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MediumTermNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-72ac-ac47-500fd81613cf" xlink:to="loc_us-gaap_MediumTermNotesMember_01a198af-cfbc-7d62-b2bb-cdea67e1a107" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a198af-cfbc-7415-8824-c43c6d1c24df" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198af-cfbc-7bcf-a098-410dd03fae36" xlink:to="loc_srt_RangeAxis_01a198af-cfbc-7415-8824-c43c6d1c24df" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a198af-cfbc-7415-8824-c43c6d1c24df_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a198af-cfbc-7415-8824-c43c6d1c24df" xlink:to="loc_srt_RangeMember_01a198af-cfbc-7415-8824-c43c6d1c24df_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a198af-cfbc-74bd-911a-780e629589bf" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a198af-cfbc-7415-8824-c43c6d1c24df" xlink:to="loc_srt_RangeMember_01a198af-cfbc-74bd-911a-780e629589bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a198af-cfbc-722a-939d-81d6844abc57" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a198af-cfbc-74bd-911a-780e629589bf" xlink:to="loc_srt_MinimumMember_01a198af-cfbc-722a-939d-81d6844abc57" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a198af-cfbc-7b0b-bffd-25ca5a8ce54a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a198af-cfbc-74bd-911a-780e629589bf" xlink:to="loc_srt_MaximumMember_01a198af-cfbc-7b0b-bffd-25ca5a8ce54a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01a198af-cfbc-792a-b34b-1eb38adfb240" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01a198af-cfbc-792a-b34b-1eb38adfb240" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_01a198af-cfbc-7ff6-be0e-fe00c1929eed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_01a198af-cfbc-7ff6-be0e-fe00c1929eed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_01a198af-cfbc-7f8e-946a-90b1041c0422" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_01a198af-cfbc-7f8e-946a-90b1041c0422" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_01a198af-cfbc-77c4-bcaf-fd185c8b67a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_LongTermDebt_01a198af-cfbc-77c4-bcaf-fd185c8b67a6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_01a198af-cfbc-7549-8163-4e6f3305338c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_01a198af-cfbc-7549-8163-4e6f3305338c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_01a198af-cfbc-72ab-8b4e-b24552a31f78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_InterestExpenseDebt_01a198af-cfbc-72ab-8b4e-b24552a31f78" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_01a198af-cfbc-79aa-9e3a-fedabb6483c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_01a198af-cfbc-79aa-9e3a-fedabb6483c6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_01a198af-cfbc-7768-93d0-8a30f55d758b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_01a198af-cfbc-7768-93d0-8a30f55d758b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_01a198af-cfbc-7f4d-9618-a17966435394" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LettersOfCreditOutstandingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_LettersOfCreditOutstandingAmount_01a198af-cfbc-7f4d-9618-a17966435394" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateDuringPeriod_01a198af-cfbc-7eaa-a01b-800b7d7b5551" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198af-cfbc-7e8f-98e3-48a9d45ff45e" xlink:to="loc_us-gaap_DebtInstrumentInterestRateDuringPeriod_01a198af-cfbc-7eaa-a01b-800b7d7b5551" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/LongTermDebtAdditionalInformationDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#LongTermDebtAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/LongTermDebtAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_01a198e9-c291-71a9-9648-fe029086fc3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_DebtInstrumentTable_01a198e9-c291-71a9-9648-fe029086fc3b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a198e9-c291-761e-a9ad-635740883ec8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198e9-c291-71a9-9648-fe029086fc3b" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a198e9-c291-761e-a9ad-635740883ec8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198e9-c291-761e-a9ad-635740883ec8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198e9-c291-761e-a9ad-635740883ec8" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198e9-c291-761e-a9ad-635740883ec8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198e9-c291-7b23-8ee6-9a94bbf681a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198e9-c291-761e-a9ad-635740883ec8" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198e9-c291-7b23-8ee6-9a94bbf681a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_FiveAndOneOverFourPercentageSeniorNotesDueMay152027Member_01a198e9-c291-7941-89eb-4bcd4cdbbfce" xlink:href="wynn-20260930.xsd#wynn_FiveAndOneOverFourPercentageSeniorNotesDueMay152027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198e9-c291-7b23-8ee6-9a94bbf681a7" xlink:to="loc_wynn_FiveAndOneOverFourPercentageSeniorNotesDueMay152027Member_01a198e9-c291-7941-89eb-4bcd4cdbbfce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_A678SeniorNotesDue2035Member_01a198f5-c218-7985-ac11-3e31ce48ec87" xlink:href="wynn-20260930.xsd#wynn_A678SeniorNotesDue2035Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198e9-c291-7b23-8ee6-9a94bbf681a7" xlink:to="loc_wynn_A678SeniorNotesDue2035Member_01a198f5-c218-7985-ac11-3e31ce48ec87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a198e9-c291-7e8b-8462-e1bba238edfb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198e9-c291-71a9-9648-fe029086fc3b" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a198e9-c291-7e8b-8462-e1bba238edfb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198e9-c291-7e8b-8462-e1bba238edfb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198e9-c291-7e8b-8462-e1bba238edfb" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198e9-c291-7e8b-8462-e1bba238edfb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198e9-c291-788d-9a3e-d23c093644a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198e9-c291-7e8b-8462-e1bba238edfb" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198e9-c291-788d-9a3e-d23c093644a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_01a198e9-c291-7c2f-a3f2-37fb86587393" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198e9-c291-788d-9a3e-d23c093644a6" xlink:to="loc_us-gaap_SeniorNotesMember_01a198e9-c291-7c2f-a3f2-37fb86587393" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198e9-c291-7864-9469-a5a373efe039" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_01a198e9-c291-71a9-9648-fe029086fc3b" xlink:to="loc_dei_LegalEntityAxis_01a198e9-c291-7864-9469-a5a373efe039" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198e9-c291-7864-9469-a5a373efe039_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198e9-c291-7864-9469-a5a373efe039" xlink:to="loc_dei_EntityDomain_01a198e9-c291-7864-9469-a5a373efe039_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198e9-c291-7ca2-9b4b-9f34226aa31a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198e9-c291-7864-9469-a5a373efe039" xlink:to="loc_dei_EntityDomain_01a198e9-c291-7ca2-9b4b-9f34226aa31a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnLasVegasLLCandWynnLasVegasCapitalCorpMember_01a198e9-c291-7b06-9c64-870e5fb150d8" xlink:href="wynn-20260930.xsd#wynn_WynnLasVegasLLCandWynnLasVegasCapitalCorpMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198e9-c291-7ca2-9b4b-9f34226aa31a" xlink:to="loc_wynn_WynnLasVegasLLCandWynnLasVegasCapitalCorpMember_01a198e9-c291-7b06-9c64-870e5fb150d8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnResortsFinanceLLCMember_01a198ea-43ed-7796-9761-9bc0cfcd2438" xlink:href="wynn-20260930.xsd#wynn_WynnResortsFinanceLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198e9-c291-7ca2-9b4b-9f34226aa31a" xlink:to="loc_wynn_WynnResortsFinanceLLCMember_01a198ea-43ed-7796-9761-9bc0cfcd2438" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnResortsMember_01a1aced-2957-7466-8967-3d0fbfa0bc19" xlink:href="wynn-20260930.xsd#wynn_WynnResortsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198e9-c291-7ca2-9b4b-9f34226aa31a" xlink:to="loc_wynn_WynnResortsMember_01a1aced-2957-7466-8967-3d0fbfa0bc19" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_01a198e4-3a9e-7c53-86ff-9c02df35b4d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_01a198e4-3a9e-7c53-86ff-9c02df35b4d5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscount_01a198e4-811f-70a9-b342-d75c77edfd49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnamortizedDiscount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscount_01a198e4-811f-70a9-b342-d75c77edfd49" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_01a198e4-b65a-76e2-9ea3-6ab323e21f52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredFinanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_01a198e4-b65a-76e2-9ea3-6ab323e21f52" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExtinguishmentOfDebtAmount_01a198e8-a21e-7d2a-8b93-8d15b2dd0d78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExtinguishmentOfDebtAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_ExtinguishmentOfDebtAmount_01a198e8-a21e-7d2a-8b93-8d15b2dd0d78" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed_01a198e8-caa5-7126-a92b-5678522b1940" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed_01a198e8-caa5-7126-a92b-5678522b1940" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a198e9-5837-7717-9bd3-772893e8f888" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a198e9-5837-7717-9bd3-772893e8f888" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFairValue_01a198af-cfbc-783a-aeaa-afe5fbdbbc8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_DebtInstrumentFairValue_01a198af-cfbc-783a-aeaa-afe5fbdbbc8a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_01a198af-cfbc-75b8-97f1-c8410ad310d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_01a198e9-c291-73e8-8bd8-6009b7c5d17f" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_01a198af-cfbc-75b8-97f1-c8410ad310d8" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/DerivativeInstrumentsValuationTechniquesforEmbeddedDerivativeDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#DerivativeInstrumentsValuationTechniquesforEmbeddedDerivativeDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/DerivativeInstrumentsValuationTechniquesforEmbeddedDerivativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_01a198af-cfbc-7435-ad44-aaf930b12dfd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_01a198af-cfbc-7f98-ac41-9eeae5d09372" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_01a198af-cfbc-7435-ad44-aaf930b12dfd" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_01a198af-cfbc-7f98-ac41-9eeae5d09372" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_01a198af-cfbc-7579-80f4-00a8cd08398f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_01a198af-cfbc-7f98-ac41-9eeae5d09372" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_01a198af-cfbc-7579-80f4-00a8cd08398f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-7579-80f4-00a8cd08398f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_01a198af-cfbc-7579-80f4-00a8cd08398f" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-7579-80f4-00a8cd08398f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-72bd-91ea-34f6cff38f7e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_01a198af-cfbc-7579-80f4-00a8cd08398f" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-72bd-91ea-34f6cff38f7e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputSharePriceMember_01a198af-cfbc-79af-bc26-733c07140af2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputSharePriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-72bd-91ea-34f6cff38f7e" xlink:to="loc_us-gaap_MeasurementInputSharePriceMember_01a198af-cfbc-79af-bc26-733c07140af2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputPriceVolatilityMember_01a198af-cfbc-768f-98fd-8cf68f9f34a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputPriceVolatilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-72bd-91ea-34f6cff38f7e" xlink:to="loc_us-gaap_MeasurementInputPriceVolatilityMember_01a198af-cfbc-768f-98fd-8cf68f9f34a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputRiskFreeInterestRateMember_01a198af-cfbc-7993-89f4-89a4534d1266" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputRiskFreeInterestRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-72bd-91ea-34f6cff38f7e" xlink:to="loc_us-gaap_MeasurementInputRiskFreeInterestRateMember_01a198af-cfbc-7993-89f4-89a4534d1266" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputExpectedTermMember_01a198af-cfbc-7057-8b33-2fcea7df3919" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputExpectedTermMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-72bd-91ea-34f6cff38f7e" xlink:to="loc_us-gaap_MeasurementInputExpectedTermMember_01a198af-cfbc-7057-8b33-2fcea7df3919" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputExpectedDividendRateMember_01a198af-cfbc-73f9-8c7e-b61a868690f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputExpectedDividendRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_01a198af-cfbc-72bd-91ea-34f6cff38f7e" xlink:to="loc_us-gaap_MeasurementInputExpectedDividendRateMember_01a198af-cfbc-73f9-8c7e-b61a868690f7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmbeddedDerivativeLiabilityMeasurementInput_01a198af-cfbc-7565-97dd-fc7add6fe0a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmbeddedDerivativeLiabilityMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_01a198af-cfbc-7435-ad44-aaf930b12dfd" xlink:to="loc_us-gaap_EmbeddedDerivativeLiabilityMeasurementInput_01a198af-cfbc-7565-97dd-fc7add6fe0a8" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/DerivativeInstrumentsNarrativeDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#DerivativeInstrumentsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/DerivativeInstrumentsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_01a198af-cfbc-721e-8f7b-1161c77719a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeTable_01a198af-cfbc-721e-8f7b-1161c77719a6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7e48-a7a5-40cdb0eef77d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_01a198af-cfbc-721e-8f7b-1161c77719a6" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7e48-a7a5-40cdb0eef77d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7e48-a7a5-40cdb0eef77d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7e48-a7a5-40cdb0eef77d" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7e48-a7a5-40cdb0eef77d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7608-9c94-f34932a62696" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_01a198af-cfbc-7e48-a7a5-40cdb0eef77d" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7608-9c94-f34932a62696" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WMLConvertibleBondsMember_01a198af-cfbc-7b5c-86d5-c7dcc6309c52" xlink:href="wynn-20260930.xsd#wynn_WMLConvertibleBondsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a198af-cfbc-7608-9c94-f34932a62696" xlink:to="loc_wynn_WMLConvertibleBondsMember_01a198af-cfbc-7b5c-86d5-c7dcc6309c52" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7d33-917f-deaa2558af92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_01a198af-cfbc-721e-8f7b-1161c77719a6" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7d33-917f-deaa2558af92" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7d33-917f-deaa2558af92_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7d33-917f-deaa2558af92" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7d33-917f-deaa2558af92_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7b24-bb92-6685ab92bd44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-7d33-917f-deaa2558af92" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7b24-bb92-6685ab92bd44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtMember_01a198af-cfbc-7a5b-a520-2e343fe2bd80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7b24-bb92-6685ab92bd44" xlink:to="loc_us-gaap_ConvertibleDebtMember_01a198af-cfbc-7a5b-a520-2e343fe2bd80" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-73d4-8248-37fedc6a1e6c" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_01a198af-cfbc-721e-8f7b-1161c77719a6" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-73d4-8248-37fedc6a1e6c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-73d4-8248-37fedc6a1e6c_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-73d4-8248-37fedc6a1e6c" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-73d4-8248-37fedc6a1e6c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-7ff3-b53e-2b2ebd2e636c" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-73d4-8248-37fedc6a1e6c" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-7ff3-b53e-2b2ebd2e636c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-777e-a332-80782c7838ef" xlink:href="wynn-20260930.xsd#wynn_WynnMacauLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-7ff3-b53e-2b2ebd2e636c" xlink:to="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-777e-a332-80782c7838ef" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-782a-aeea-319179dfbe02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_01a198af-cfbc-721e-8f7b-1161c77719a6" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-782a-aeea-319179dfbe02" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-782a-aeea-319179dfbe02_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-782a-aeea-319179dfbe02" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-782a-aeea-319179dfbe02_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-7fb9-aa0f-cbe09b688187" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-782a-aeea-319179dfbe02" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-7fb9-aa0f-cbe09b688187" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_CurrencySwapJanuary2026Member_01a198af-cfbc-79bf-8267-ac1139c0743f" xlink:href="wynn-20260930.xsd#wynn_CurrencySwapJanuary2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-7fb9-aa0f-cbe09b688187" xlink:to="loc_wynn_CurrencySwapJanuary2026Member_01a198af-cfbc-79bf-8267-ac1139c0743f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_01a198af-cfbc-7367-abe9-9193ff16507e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-7fb9-aa0f-cbe09b688187" xlink:to="loc_us-gaap_CurrencySwapMember_01a198af-cfbc-7367-abe9-9193ff16507e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_01a198af-cfbc-7ea0-805b-722764d4a8d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeLiabilities_01a198af-cfbc-7ea0-805b-722764d4a8d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet_01a198af-cfbc-7239-b26b-1bcf51e28944" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet_01a198af-cfbc-7239-b26b-1bcf51e28944" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_01a198af-cfbc-74ad-b4fd-24566efc23fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeNotionalAmount_01a198af-cfbc-74ad-b4fd-24566efc23fa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_01a198af-cfbc-7726-8aee-614fb5cfd1a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeAssets_01a198af-cfbc-7726-8aee-614fb5cfd1a9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_01a198af-cfbc-7681-9e62-a1dab4cbab24" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_01a198af-cfbc-7681-9e62-a1dab4cbab24" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsNoncurrent_01a198ec-a1b3-79ce-9a33-9483537d7dff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeAssetsNoncurrent_01a198ec-a1b3-79ce-9a33-9483537d7dff" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilitiesNoncurrent_01a198af-cfbc-7f4f-8c5b-de5eec658aff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilitiesNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeLiabilitiesNoncurrent_01a198af-cfbc-7f4f-8c5b-de5eec658aff" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet_01a198af-cfbc-70c9-9235-74d82124c869" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeGainLossOnDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_01a198af-cfbc-7845-b00e-3bde2323694c" xlink:to="loc_us-gaap_DerivativeGainLossOnDerivativeNet_01a198af-cfbc-70c9-9235-74d82124c869" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/StockholdersDeficitDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#StockholdersDeficitDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/StockholdersDeficitDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiarySaleOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_01a198af-cfbc-7a65-b50c-38818a6af435" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_srt_ShareRepurchaseProgramAxis_01a198af-cfbc-7a65-b50c-38818a6af435" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a198af-cfbc-7a65-b50c-38818a6af435_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a198af-cfbc-7a65-b50c-38818a6af435" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a198af-cfbc-7a65-b50c-38818a6af435_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a198af-cfbc-716e-a6b7-9a89a188f9dc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a198af-cfbc-7a65-b50c-38818a6af435" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a198af-cfbc-716e-a6b7-9a89a188f9dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_April2016EquityRepurchaseProgramMember_01a198af-cfbc-78e2-87f5-41519188b3cc" xlink:href="wynn-20260930.xsd#wynn_April2016EquityRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a198af-cfbc-716e-a6b7-9a89a188f9dc" xlink:to="loc_wynn_April2016EquityRepurchaseProgramMember_01a198af-cfbc-78e2-87f5-41519188b3cc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsAxis_01a198af-cfbc-7b8e-9e14-85d9b1396cb9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_us-gaap_DividendsAxis_01a198af-cfbc-7b8e-9e14-85d9b1396cb9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsDomain_01a198af-cfbc-7b8e-9e14-85d9b1396cb9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DividendsAxis_01a198af-cfbc-7b8e-9e14-85d9b1396cb9" xlink:to="loc_us-gaap_DividendsDomain_01a198af-cfbc-7b8e-9e14-85d9b1396cb9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DividendsAxis_01a198af-cfbc-7b8e-9e14-85d9b1396cb9" xlink:to="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_O2026Q1DividendsMember_01a198af-cfbc-7d4e-bad0-5e0dd2ad57ae" xlink:href="wynn-20260930.xsd#wynn_O2026Q1DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:to="loc_wynn_O2026Q1DividendsMember_01a198af-cfbc-7d4e-bad0-5e0dd2ad57ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_O2026Q2DividendsMember_01a198af-cfbc-783b-aaa2-efc94c24d8a4" xlink:href="wynn-20260930.xsd#wynn_O2026Q2DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:to="loc_wynn_O2026Q2DividendsMember_01a198af-cfbc-783b-aaa2-efc94c24d8a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_O2026Q3DividendsMember_01a198ee-fb51-771e-bce8-c7ea5f8b4f3b" xlink:href="wynn-20260930.xsd#wynn_O2026Q3DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:to="loc_wynn_O2026Q3DividendsMember_01a198ee-fb51-771e-bce8-c7ea5f8b4f3b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_O2025Q1DividendsMember_01a198af-cfbc-7666-b801-1760488fcee5" xlink:href="wynn-20260930.xsd#wynn_O2025Q1DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:to="loc_wynn_O2025Q1DividendsMember_01a198af-cfbc-7666-b801-1760488fcee5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_O2025Q2DividendsMember_01a198af-cfbc-77b0-8031-04092f74adf8" xlink:href="wynn-20260930.xsd#wynn_O2025Q2DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:to="loc_wynn_O2025Q2DividendsMember_01a198af-cfbc-77b0-8031-04092f74adf8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_O2025Q3DividendsMember_01a198ef-cd53-7f44-bee7-1a86a5e4b58a" xlink:href="wynn-20260930.xsd#wynn_O2025Q3DividendsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DividendsDomain_01a198af-cfbc-7a0e-8312-eaadad5338b5" xlink:to="loc_wynn_O2025Q3DividendsMember_01a198ef-cd53-7f44-bee7-1a86a5e4b58a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7d7b-86ad-cc6e6a844a4b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7d7b-86ad-cc6e6a844a4b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7d7b-86ad-cc6e6a844a4b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7d7b-86ad-cc6e6a844a4b" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7d7b-86ad-cc6e6a844a4b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-74c7-bff8-ff433a2f90e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7d7b-86ad-cc6e6a844a4b" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-74c7-bff8-ff433a2f90e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_01a198af-cfbc-7d6b-bc06-13b7bd890402" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-74c7-bff8-ff433a2f90e6" xlink:to="loc_us-gaap_SubsequentEventMember_01a198af-cfbc-7d6b-bc06-13b7bd890402" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_01a198af-cfbc-722a-a4f2-8ba64f3f6ad9" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_srt_ConsolidatedEntitiesAxis_01a198af-cfbc-722a-a4f2-8ba64f3f6ad9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_01a198af-cfbc-722a-a4f2-8ba64f3f6ad9_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_01a198af-cfbc-722a-a4f2-8ba64f3f6ad9" xlink:to="loc_srt_ConsolidatedEntitiesDomain_01a198af-cfbc-722a-a4f2-8ba64f3f6ad9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_01a198af-cfbc-76a5-94a2-c29f08c1daba" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_01a198af-cfbc-722a-a4f2-8ba64f3f6ad9" xlink:to="loc_srt_ConsolidatedEntitiesDomain_01a198af-cfbc-76a5-94a2-c29f08c1daba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SubsidiariesMember_01a198af-cfbc-75e6-a8de-d7cf0d042a07" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SubsidiariesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_01a198af-cfbc-76a5-94a2-c29f08c1daba" xlink:to="loc_srt_SubsidiariesMember_01a198af-cfbc-75e6-a8de-d7cf0d042a07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-7673-9be5-c974ad5fe9a7" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-7673-9be5-c974ad5fe9a7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-7673-9be5-c974ad5fe9a7_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7673-9be5-c974ad5fe9a7" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-7673-9be5-c974ad5fe9a7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-730e-ab7e-d2dde5d46808" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7673-9be5-c974ad5fe9a7" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-730e-ab7e-d2dde5d46808" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-7bd1-848b-4ec8a3e66906" xlink:href="wynn-20260930.xsd#wynn_WynnMacauLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-730e-ab7e-d2dde5d46808" xlink:to="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-7bd1-848b-4ec8a3e66906" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WMCaymanIMember_01a198af-cfbc-7365-8d34-3ed51830e439" xlink:href="wynn-20260930.xsd#wynn_WMCaymanIMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-730e-ab7e-d2dde5d46808" xlink:to="loc_wynn_WMCaymanIMember_01a198af-cfbc-7365-8d34-3ed51830e439" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_01a198af-cfbc-74fa-9b22-0ea352115ed2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_srt_OwnershipAxis_01a198af-cfbc-74fa-9b22-0ea352115ed2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-74fa-9b22-0ea352115ed2_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-74fa-9b22-0ea352115ed2" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-74fa-9b22-0ea352115ed2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-731e-b2cb-4fa36f1f2cd0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-74fa-9b22-0ea352115ed2" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-731e-b2cb-4fa36f1f2cd0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnPalaceandWynnMacauMember_01a198af-cfbc-7846-a0ea-6cb3287dffb5" xlink:href="wynn-20260930.xsd#wynn_WynnPalaceandWynnMacauMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_01a198af-cfbc-731e-b2cb-4fa36f1f2cd0" xlink:to="loc_wynn_WynnPalaceandWynnMacauMember_01a198af-cfbc-7846-a0ea-6cb3287dffb5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_01a198af-cfbc-72f0-8f8b-7eea2d1b3038" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_srt_CounterpartyNameAxis_01a198af-cfbc-72f0-8f8b-7eea2d1b3038" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-72f0-8f8b-7eea2d1b3038_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_01a198af-cfbc-72f0-8f8b-7eea2d1b3038" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-72f0-8f8b-7eea2d1b3038_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-76b6-9885-7a5473176c9a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_01a198af-cfbc-72f0-8f8b-7eea2d1b3038" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-76b6-9885-7a5473176c9a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-7d0f-8bd6-995f85e3f47a" xlink:href="wynn-20260930.xsd#wynn_WynnMacauLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-76b6-9885-7a5473176c9a" xlink:to="loc_wynn_WynnMacauLimitedMember_01a198af-cfbc-7d0f-8bd6-995f85e3f47a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_GoldmanSachsInternationalMember_01a198af-cfbc-7f2d-9551-37f6733e30b3" xlink:href="wynn-20260930.xsd#wynn_GoldmanSachsInternationalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-76b6-9885-7a5473176c9a" xlink:to="loc_wynn_GoldmanSachsInternationalMember_01a198af-cfbc-7f2d-9551-37f6733e30b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_01a198af-cfbc-74d2-92ed-88e7106c9437" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_01a198af-cfbc-725b-9ed5-9d2bb90f46f4" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_01a198af-cfbc-74d2-92ed-88e7106c9437" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_01a198af-cfbc-74d2-92ed-88e7106c9437_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_01a198af-cfbc-74d2-92ed-88e7106c9437" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_01a198af-cfbc-74d2-92ed-88e7106c9437_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_01a198af-cfbc-79f2-a9ff-3ca8ac6d8fb2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_01a198af-cfbc-74d2-92ed-88e7106c9437" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_01a198af-cfbc-79f2-a9ff-3ca8ac6d8fb2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_SecuritiesLendingAgreementMember_01a198af-cfbc-7863-8766-b4e5f8f31468" xlink:href="wynn-20260930.xsd#wynn_SecuritiesLendingAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_01a198af-cfbc-79f2-a9ff-3ca8ac6d8fb2" xlink:to="loc_wynn_SecuritiesLendingAgreementMember_01a198af-cfbc-7863-8766-b4e5f8f31468" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_01a198af-cfbc-72b3-96bb-013cd759005d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_01a198af-cfbc-72b3-96bb-013cd759005d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_01a198af-cfbc-7301-a00e-720c00065bd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_01a198af-cfbc-7301-a00e-720c00065bd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a198af-cfbc-7338-b07b-80ced3065f52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a198af-cfbc-7338-b07b-80ced3065f52" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a198af-cfbc-7d32-be56-877d2513ea5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_01a198af-cfbc-7d32-be56-877d2513ea5c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_01a198af-cfbc-700d-8ff1-66a75349ed41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_01a198af-cfbc-700d-8ff1-66a75349ed41" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareCashPaid_01a198af-cfbc-71e0-b1ce-3b90f379be92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockDividendsPerShareCashPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_CommonStockDividendsPerShareCashPaid_01a198af-cfbc-71e0-b1ce-3b90f379be92" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockCash_01a198af-cfbc-72fc-89e4-a0b3f5fadc9c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStockCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_DividendsCommonStockCash_01a198af-cfbc-72fc-89e4-a0b3f5fadc9c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPayableAmountPerShare_01a198af-cfbc-799e-ad15-eda32b128eaa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsPayableAmountPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_DividendsPayableAmountPerShare_01a198af-cfbc-799e-ad15-eda32b128eaa" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestOwnershipPercentageByParent_01a198af-cfbc-7209-9c4c-325955fb3ea6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestOwnershipPercentageByParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_MinorityInterestOwnershipPercentageByParent_01a198af-cfbc-7209-9c4c-325955fb3ea6" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_01a198af-cfbc-76e1-87d7-d398044da209" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_01a198af-cfbc-76e1-87d7-d398044da209" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_01a198af-cfbc-75e9-960f-f6deca9267a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_01a198af-cfbc-75e9-960f-f6deca9267a3" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDistributionsToAffiliates_01a198af-cfbc-7173-bddb-20e6bb6fc09f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfDistributionsToAffiliates"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_PaymentsOfDistributionsToAffiliates_01a198af-cfbc-7173-bddb-20e6bb6fc09f" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCash_01a198af-cfbc-7edf-894a-eca987b88b1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_DividendsCash_01a198af-cfbc-7edf-894a-eca987b88b1a" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromDividendsReceived_01a198af-cfbc-7015-8516-6059cc947c2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromDividendsReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_ProceedsFromDividendsReceived_01a198af-cfbc-7015-8516-6059cc947c2b" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_01a198af-cfbc-7367-be81-fd84897de23d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems_01a198af-cfbc-745b-8a4c-7036205a7ce8" xlink:to="loc_us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders_01a198af-cfbc-7367-be81-fd84897de23d" xlink:type="arc" order="14"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/FairValueMeasurementsDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#FairValueMeasurementsDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/FairValueMeasurementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a198af-cfbc-7aad-a5f6-7eec9df97114" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a198af-cfbc-7742-9f9e-009873a14e1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a198af-cfbc-7aad-a5f6-7eec9df97114" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a198af-cfbc-7742-9f9e-009873a14e1a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a198af-cfbc-7816-9677-e75592e086e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a198af-cfbc-7742-9f9e-009873a14e1a" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a198af-cfbc-7816-9677-e75592e086e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a198af-cfbc-7816-9677-e75592e086e8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a198af-cfbc-7816-9677-e75592e086e8" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a198af-cfbc-7816-9677-e75592e086e8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a198af-cfbc-733d-9eb8-8c5237807e5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a198af-cfbc-7816-9677-e75592e086e8" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a198af-cfbc-733d-9eb8-8c5237807e5c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_01a198af-cfbc-7576-97eb-26f558129ce7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a198af-cfbc-733d-9eb8-8c5237807e5c" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_01a198af-cfbc-7576-97eb-26f558129ce7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a198af-cfbc-767e-ad1e-76ebf1e8d767" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a198af-cfbc-7742-9f9e-009873a14e1a" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a198af-cfbc-767e-ad1e-76ebf1e8d767" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a198af-cfbc-767e-ad1e-76ebf1e8d767_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a198af-cfbc-767e-ad1e-76ebf1e8d767" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a198af-cfbc-767e-ad1e-76ebf1e8d767_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a198af-cfbc-7c54-97c8-fa10b0924df0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a198af-cfbc-767e-ad1e-76ebf1e8d767" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a198af-cfbc-7c54-97c8-fa10b0924df0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_01a198af-cfbc-75c5-ad65-4b3175a2db03" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a198af-cfbc-7c54-97c8-fa10b0924df0" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_01a198af-cfbc-75c5-ad65-4b3175a2db03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_01a198af-cfbc-7d05-86ec-74e1c9dcc254" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a198af-cfbc-7c54-97c8-fa10b0924df0" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_01a198af-cfbc-7d05-86ec-74e1c9dcc254" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_01a198af-cfbc-71ec-bfb7-c33723cb00ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a198af-cfbc-7c54-97c8-fa10b0924df0" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_01a198af-cfbc-71ec-bfb7-c33723cb00ab" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-722d-a600-08d720c87ad7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a198af-cfbc-7742-9f9e-009873a14e1a" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-722d-a600-08d720c87ad7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-722d-a600-08d720c87ad7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-722d-a600-08d720c87ad7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-722d-a600-08d720c87ad7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-70ce-8de5-9eeb3141f3eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198af-cfbc-722d-a600-08d720c87ad7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-70ce-8de5-9eeb3141f3eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WMLConvertibleBondConversionOptionDerivativeMember_01a198af-cfbc-79b4-958a-ebce7b417ed7" xlink:href="wynn-20260930.xsd#wynn_WMLConvertibleBondConversionOptionDerivativeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-70ce-8de5-9eeb3141f3eb" xlink:to="loc_wynn_WMLConvertibleBondConversionOptionDerivativeMember_01a198af-cfbc-79b4-958a-ebce7b417ed7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrencySwapMember_01a198af-cfbc-79ae-86dd-ca82006fde22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CurrencySwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-70ce-8de5-9eeb3141f3eb" xlink:to="loc_us-gaap_CurrencySwapMember_01a198af-cfbc-79ae-86dd-ca82006fde22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_01a1a298-49e1-77d0-936f-276f65da8de1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-70ce-8de5-9eeb3141f3eb" xlink:to="loc_us-gaap_InterestRateContractMember_01a1a298-49e1-77d0-936f-276f65da8de1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_01a198af-cfbc-7d0e-8368-51f130ad43ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198af-cfbc-70ce-8de5-9eeb3141f3eb" xlink:to="loc_us-gaap_InterestRateSwapMember_01a198af-cfbc-7d0e-8368-51f130ad43ce" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a198af-cfbc-73aa-9099-4e9f49ecd632" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a198af-cfbc-7aad-a5f6-7eec9df97114" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a198af-cfbc-73aa-9099-4e9f49ecd632" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsAtCarryingValue_01a198af-cfbc-77d9-be6f-c7a3f7547e9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a198af-cfbc-73aa-9099-4e9f49ecd632" xlink:to="loc_us-gaap_CashEquivalentsAtCarryingValue_01a198af-cfbc-77d9-be6f-c7a3f7547e9e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalents_01a198af-cfbc-706a-9966-8c8ba02328ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a198af-cfbc-73aa-9099-4e9f49ecd632" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalents_01a198af-cfbc-706a-9966-8c8ba02328ab" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_InvestmentsFixedDepositsFairValueDisclosure_01a198af-cfbc-7617-8853-8143451b5c2c" xlink:href="wynn-20260930.xsd#wynn_InvestmentsFixedDepositsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a198af-cfbc-73aa-9099-4e9f49ecd632" xlink:to="loc_wynn_InvestmentsFixedDepositsFairValueDisclosure_01a198af-cfbc-7617-8853-8143451b5c2c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_01a198af-cfbc-7478-8f06-244fc3a5812f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a198af-cfbc-73aa-9099-4e9f49ecd632" xlink:to="loc_us-gaap_DerivativeAssets_01a198af-cfbc-7478-8f06-244fc3a5812f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a198af-cfbc-7faa-8c5d-e1532394b7af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a198af-cfbc-7aad-a5f6-7eec9df97114" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a198af-cfbc-7faa-8c5d-e1532394b7af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_01a198af-cfbc-75a9-a163-1679803105c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a198af-cfbc-7faa-8c5d-e1532394b7af" xlink:to="loc_us-gaap_DerivativeLiabilities_01a198af-cfbc-75a9-a163-1679803105c3" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/StockBasedCompensationShareBasedCompensationAllocatedCostsDetail" xlink:type="simple" xlink:href="wynn-20260930.xsd#StockBasedCompensationShareBasedCompensationAllocatedCostsDetail"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/StockBasedCompensationShareBasedCompensationAllocatedCostsDetail" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_01a198af-cfbc-7a2a-bac0-116e8db7b22b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_01a198af-cfbc-7afe-bd13-b4d32d855a34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_01a198af-cfbc-7a2a-bac0-116e8db7b22b" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_01a198af-cfbc-7afe-bd13-b4d32d855a34" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7256-8024-fa8f679fd96e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_01a198af-cfbc-7afe-bd13-b4d32d855a34" xlink:to="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7256-8024-fa8f679fd96e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7256-8024-fa8f679fd96e_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7256-8024-fa8f679fd96e" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7256-8024-fa8f679fd96e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7e26-9281-4220c24d46df" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7256-8024-fa8f679fd96e" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7e26-9281-4220c24d46df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CasinoMember_01a198af-cfbc-7a89-877f-4559f99db49d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CasinoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7e26-9281-4220c24d46df" xlink:to="loc_us-gaap_CasinoMember_01a198af-cfbc-7a89-877f-4559f99db49d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_RoomsMember_01a198af-cfbc-7f0a-9418-dc65d20bdbe5" xlink:href="wynn-20260930.xsd#wynn_RoomsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7e26-9281-4220c24d46df" xlink:to="loc_wynn_RoomsMember_01a198af-cfbc-7f0a-9418-dc65d20bdbe5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FoodAndBeverageMember_01a198af-cfbc-7758-9068-7af6bf7555f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FoodAndBeverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7e26-9281-4220c24d46df" xlink:to="loc_us-gaap_FoodAndBeverageMember_01a198af-cfbc-7758-9068-7af6bf7555f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EntertainmentRetailAndOtherMember_01a198af-cfbc-775d-91af-56f49b7429d9" xlink:href="wynn-20260930.xsd#wynn_EntertainmentRetailAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7e26-9281-4220c24d46df" xlink:to="loc_wynn_EntertainmentRetailAndOtherMember_01a198af-cfbc-775d-91af-56f49b7429d9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_GeneralAndAdministrativeMember_01a198af-cfbc-79b6-8376-c8aa522f18d4" xlink:href="wynn-20260930.xsd#wynn_GeneralAndAdministrativeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7e26-9281-4220c24d46df" xlink:to="loc_wynn_GeneralAndAdministrativeMember_01a198af-cfbc-79b6-8376-c8aa522f18d4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_01a198af-cfbc-78c8-b14e-53acf8fd7f04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_01a198af-cfbc-7a2a-bac0-116e8db7b22b" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_01a198af-cfbc-78c8-b14e-53acf8fd7f04" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_01a198af-cfbc-7236-8d19-f90c547280df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_01a198af-cfbc-7a2a-bac0-116e8db7b22b" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_01a198af-cfbc-7236-8d19-f90c547280df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_01a198af-cfbc-7b36-88b2-1cba3d4553dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_01a198af-cfbc-7a2a-bac0-116e8db7b22b" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_01a198af-cfbc-7b36-88b2-1cba3d4553dc" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/CommitmentsandContingenciesDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#CommitmentsandContingenciesDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/CommitmentsandContingenciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-79b5-b0d3-f66a577d3f25_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-79b5-b0d3-f66a577d3f25_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-7991-83eb-00a9aec64b86" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-7991-83eb-00a9aec64b86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnAlMarjanIslandMember_01a198af-cfbc-76ba-9e1f-f5201ebc1feb" xlink:href="wynn-20260930.xsd#wynn_WynnAlMarjanIslandMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_01a198af-cfbc-7991-83eb-00a9aec64b86" xlink:to="loc_wynn_WynnAlMarjanIslandMember_01a198af-cfbc-76ba-9e1f-f5201ebc1feb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a198af-cfbc-7131-987a-11556ab9e294_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:to="loc_srt_RangeMember_01a198af-cfbc-7131-987a-11556ab9e294_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:to="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a198af-cfbc-7bb9-8723-97b15984bc10" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:to="loc_srt_MinimumMember_01a198af-cfbc-7bb9-8723-97b15984bc10" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a198af-cfbc-7a44-aa9e-bc81eb844084" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:to="loc_srt_MaximumMember_01a198af-cfbc-7a44-aa9e-bc81eb844084" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fb-ab97-97d5ed78a2f8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:to="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fb-ab97-97d5ed78a2f8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fd-b8ee-081d8d6516ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:to="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fd-b8ee-081d8d6516ea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DelayedDrawSecuredTermLoanFacilityMember_01a198af-cfbc-7d31-a418-02e012272142" xlink:href="wynn-20260930.xsd#wynn_DelayedDrawSecuredTermLoanFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fd-b8ee-081d8d6516ea" xlink:to="loc_wynn_DelayedDrawSecuredTermLoanFacilityMember_01a198af-cfbc-7d31-a418-02e012272142" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-724f-ae15-1570c19cc381_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-724f-ae15-1570c19cc381_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7ae9-946e-96196a6e76dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7ae9-946e-96196a6e76dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_01a198af-cfbc-7cd2-84e9-24237c220817" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7ae9-946e-96196a6e76dc" xlink:to="loc_us-gaap_LineOfCreditMember_01a198af-cfbc-7cd2-84e9-24237c220817" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-79d0-83e0-db199a98e86f_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-79d0-83e0-db199a98e86f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnAlMarjanIslandFZLLCMember_01a198af-cfbc-77f8-9f78-300d084cb945" xlink:href="wynn-20260930.xsd#wynn_WynnAlMarjanIslandFZLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_WynnAlMarjanIslandFZLLCMember_01a198af-cfbc-77f8-9f78-300d084cb945" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_AlMarjanGuarantorsMember_01a198af-cfbc-7db4-9e7c-c8b3ad5caf8f" xlink:href="wynn-20260930.xsd#wynn_AlMarjanGuarantorsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_AlMarjanGuarantorsMember_01a198af-cfbc-7db4-9e7c-c8b3ad5caf8f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaloRealEstateCompanyLimitedPaloAndWynnMacauSAMember_01a198af-cfbc-77c6-861d-ccf40270f43a" xlink:href="wynn-20260930.xsd#wynn_PaloRealEstateCompanyLimitedPaloAndWynnMacauSAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_PaloRealEstateCompanyLimitedPaloAndWynnMacauSAMember_01a198af-cfbc-77c6-861d-ccf40270f43a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaloRealEstateCompanyLimitedPaloMember_01a198af-cfbc-736e-80f9-6abd89d2f351" xlink:href="wynn-20260930.xsd#wynn_PaloRealEstateCompanyLimitedPaloMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_PaloRealEstateCompanyLimitedPaloMember_01a198af-cfbc-736e-80f9-6abd89d2f351" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-70a1-aed0-0377679b74a4_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-70a1-aed0-0377679b74a4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7f62-9b18-22ef9a81256d" xlink:href="wynn-20260930.xsd#wynn_DCPAMI3FZLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:to="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7f62-9b18-22ef9a81256d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_MacauGovernmentMember_01a198af-cfbc-7b37-84ff-844067d83427" xlink:href="wynn-20260930.xsd#wynn_MacauGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:to="loc_wynn_MacauGovernmentMember_01a198af-cfbc-7b37-84ff-844067d83427" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-70a3-8b19-41f7030eafd3_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-70a3-8b19-41f7030eafd3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7c7d-8a6e-2c464d12c9da" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7c7d-8a6e-2c464d12c9da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7c6c-89c4-3801efbad536" xlink:href="wynn-20260930.xsd#wynn_DCPAMI3FZLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7c7d-8a6e-2c464d12c9da" xlink:to="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7c6c-89c4-3801efbad536" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7a1b-a5e9-042e01b2929f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7a1b-a5e9-042e01b2929f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7096-b0a7-c048655b9b3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7096-b0a7-c048655b9b3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_01a198af-cfbc-72a3-8cbe-216259e30cbb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7096-b0a7-c048655b9b3a" xlink:to="loc_us-gaap_SubsequentEventMember_01a198af-cfbc-72a3-8cbe-216259e30cbb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-7f98-a86a-d0ff13a9e4dd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-7f98-a86a-d0ff13a9e4dd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-71af-9cfe-eb8e78af4bba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-71af-9cfe-eb8e78af4bba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_01a198f8-2826-7a84-bbad-687dbf4f1c39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-71af-9cfe-eb8e78af4bba" xlink:to="loc_us-gaap_InterestRateContractMember_01a198f8-2826-7a84-bbad-687dbf4f1c39" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-77f2-9b9e-7923e314e7ef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:to="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-77f2-9b9e-7923e314e7ef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:to="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EmiratesInterbankOfferedRateMember_01a198f9-50a4-789e-a23c-d131f3cc10a7" xlink:href="wynn-20260930.xsd#wynn_EmiratesInterbankOfferedRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:to="loc_wynn_EmiratesInterbankOfferedRateMember_01a198f9-50a4-789e-a23c-d131f3cc10a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_01a198f9-9925-7791-8ca8-1eb274f49dd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_01a198f9-9925-7791-8ca8-1eb274f49dd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfFinancialPositionLocationBalanceAxis_01a198fa-fe23-7f51-b750-6bb77cf3db90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfFinancialPositionLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_StatementOfFinancialPositionLocationBalanceAxis_01a198fa-fe23-7f51-b750-6bb77cf3db90" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7989-8a0e-e9e372f6bf32_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:to="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7989-8a0e-e9e372f6bf32_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7a5d-8967-84a145426ccc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:to="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7a5d-8967-84a145426ccc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_MacauGovernmentInvestmentFundCapitalCommitmentsMember_01a198fd-6aec-71ba-ab84-5a1998393b35" xlink:href="wynn-20260930.xsd#wynn_MacauGovernmentInvestmentFundCapitalCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7a5d-8967-84a145426ccc" xlink:to="loc_wynn_MacauGovernmentInvestmentFundCapitalCommitmentsMember_01a198fd-6aec-71ba-ab84-5a1998393b35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyContributedCapitalToCommittedCapitalRatio_01a198af-cfbc-7177-99ca-0f238bb0de00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyContributedCapitalToCommittedCapitalRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_InvestmentCompanyContributedCapitalToCommittedCapitalRatio_01a198af-cfbc-7177-99ca-0f238bb0de00" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaymentsForContributedCapital_01a198af-cfbc-7aa7-9902-04f58f9c7f0d" xlink:href="wynn-20260930.xsd#wynn_PaymentsForContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_PaymentsForContributedCapital_01a198af-cfbc-7aa7-9902-04f58f9c7f0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyCommittedCapital_01a198af-cfbc-751f-962f-b3d24e61bab5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyCommittedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_InvestmentCompanyCommittedCapital_01a198af-cfbc-751f-962f-b3d24e61bab5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a198af-cfbc-7bc9-bac4-abcaae25d2bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a198af-cfbc-7bc9-bac4-abcaae25d2bf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableNet_01a198af-cfbc-7ebd-9d33-1884a11c70c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotesReceivableNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_NotesReceivableNet_01a198af-cfbc-7ebd-9d33-1884a11c70c7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_01a198af-cfbc-7005-a8e2-fd0ac840b6ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_EquityMethodInvestments_01a198af-cfbc-7005-a8e2-fd0ac840b6ae" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OperatingLeaseArea_01a198af-cfbc-7385-912f-9191db6f81ef" xlink:href="wynn-20260930.xsd#wynn_OperatingLeaseArea"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_OperatingLeaseArea_01a198af-cfbc-7385-912f-9191db6f81ef" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseTermOfContract_01a198af-cfbc-723a-9ce3-4765adef65d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_LesseeOperatingLeaseTermOfContract_01a198af-cfbc-723a-9ce3-4765adef65d0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaymentsToAcquireOperatingLease_01a198af-cfbc-7fc3-a007-da18dbb31971" xlink:href="wynn-20260930.xsd#wynn_PaymentsToAcquireOperatingLease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_PaymentsToAcquireOperatingLease_01a198af-cfbc-7fc3-a007-da18dbb31971" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseExpense_01a198af-cfbc-7382-9030-65cc1cdd4824" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_OperatingLeaseExpense_01a198af-cfbc-7382-9030-65cc1cdd4824" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DerivativeNotionalAmountPercentageEqualToDebtFaceAmount_01a198f7-74f5-7242-8bdc-7abd053dac86" xlink:href="wynn-20260930.xsd#wynn_DerivativeNotionalAmountPercentageEqualToDebtFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_DerivativeNotionalAmountPercentageEqualToDebtFaceAmount_01a198f7-74f5-7242-8bdc-7abd053dac86" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeVariableInterestRate_01a198f8-f834-744d-89d8-bb4d0bbd790d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeVariableInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_DerivativeVariableInterestRate_01a198f8-f834-744d-89d8-bb4d0bbd790d" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_01a198fa-0f57-7fc2-a2d0-6acb7dc41ee3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_DerivativeAssets_01a198fa-0f57-7fc2-a2d0-6acb7dc41ee3" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_01a198fa-c762-7329-bc66-028f38c2abdf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_DerivativeLiabilities_01a198fa-c762-7329-bc66-028f38c2abdf" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198fc-032d-75b6-bed8-a3deb302cb75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDerivativeInstrumentsNetPretax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198fc-032d-75b6-bed8-a3deb302cb75" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitment_01a198fd-04bf-7b46-a7c1-2534df0b7e47" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_OtherCommitment_01a198fd-04bf-7b46-a7c1-2534df0b7e47" xlink:type="arc" order="15"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/CommitmentsandContingenciesDetails_1" xlink:type="simple" xlink:href="wynn-20260930.xsd#CommitmentsandContingenciesDetails_1"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/CommitmentsandContingenciesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-79b5-b0d3-f66a577d3f25_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-79b5-b0d3-f66a577d3f25_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a198af-cfbc-7991-83eb-00a9aec64b86" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_01a198af-cfbc-79b5-b0d3-f66a577d3f25" xlink:to="loc_srt_OwnershipDomain_01a198af-cfbc-7991-83eb-00a9aec64b86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnAlMarjanIslandMember_01a198af-cfbc-76ba-9e1f-f5201ebc1feb" xlink:href="wynn-20260930.xsd#wynn_WynnAlMarjanIslandMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_01a198af-cfbc-7991-83eb-00a9aec64b86" xlink:to="loc_wynn_WynnAlMarjanIslandMember_01a198af-cfbc-76ba-9e1f-f5201ebc1feb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a198af-cfbc-7131-987a-11556ab9e294_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:to="loc_srt_RangeMember_01a198af-cfbc-7131-987a-11556ab9e294_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a198af-cfbc-7131-987a-11556ab9e294" xlink:to="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a198af-cfbc-7bb9-8723-97b15984bc10" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:to="loc_srt_MinimumMember_01a198af-cfbc-7bb9-8723-97b15984bc10" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a198af-cfbc-7a44-aa9e-bc81eb844084" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a198af-cfbc-7f52-a959-98bc44a07124" xlink:to="loc_srt_MaximumMember_01a198af-cfbc-7a44-aa9e-bc81eb844084" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fb-ab97-97d5ed78a2f8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:to="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fb-ab97-97d5ed78a2f8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fd-b8ee-081d8d6516ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_01a198af-cfbc-72fb-ab97-97d5ed78a2f8" xlink:to="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fd-b8ee-081d8d6516ea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DelayedDrawSecuredTermLoanFacilityMember_01a198af-cfbc-7d31-a418-02e012272142" xlink:href="wynn-20260930.xsd#wynn_DelayedDrawSecuredTermLoanFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01a198af-cfbc-72fd-b8ee-081d8d6516ea" xlink:to="loc_wynn_DelayedDrawSecuredTermLoanFacilityMember_01a198af-cfbc-7d31-a418-02e012272142" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-724f-ae15-1570c19cc381_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-724f-ae15-1570c19cc381_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7ae9-946e-96196a6e76dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_01a198af-cfbc-724f-ae15-1570c19cc381" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7ae9-946e-96196a6e76dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_01a198af-cfbc-7cd2-84e9-24237c220817" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a198af-cfbc-7ae9-946e-96196a6e76dc" xlink:to="loc_us-gaap_LineOfCreditMember_01a198af-cfbc-7cd2-84e9-24237c220817" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-79d0-83e0-db199a98e86f_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-79d0-83e0-db199a98e86f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-79d0-83e0-db199a98e86f" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnAlMarjanIslandFZLLCMember_01a198af-cfbc-77f8-9f78-300d084cb945" xlink:href="wynn-20260930.xsd#wynn_WynnAlMarjanIslandFZLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_WynnAlMarjanIslandFZLLCMember_01a198af-cfbc-77f8-9f78-300d084cb945" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_AlMarjanGuarantorsMember_01a198af-cfbc-7db4-9e7c-c8b3ad5caf8f" xlink:href="wynn-20260930.xsd#wynn_AlMarjanGuarantorsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_AlMarjanGuarantorsMember_01a198af-cfbc-7db4-9e7c-c8b3ad5caf8f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaloRealEstateCompanyLimitedPaloAndWynnMacauSAMember_01a198af-cfbc-77c6-861d-ccf40270f43a" xlink:href="wynn-20260930.xsd#wynn_PaloRealEstateCompanyLimitedPaloAndWynnMacauSAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_PaloRealEstateCompanyLimitedPaloAndWynnMacauSAMember_01a198af-cfbc-77c6-861d-ccf40270f43a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaloRealEstateCompanyLimitedPaloMember_01a198af-cfbc-736e-80f9-6abd89d2f351" xlink:href="wynn-20260930.xsd#wynn_PaloRealEstateCompanyLimitedPaloMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-72df-afe8-c297eea29d65" xlink:to="loc_wynn_PaloRealEstateCompanyLimitedPaloMember_01a198af-cfbc-736e-80f9-6abd89d2f351" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-70a1-aed0-0377679b74a4_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-70a1-aed0-0377679b74a4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_01a198af-cfbc-70a1-aed0-0377679b74a4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7f62-9b18-22ef9a81256d" xlink:href="wynn-20260930.xsd#wynn_DCPAMI3FZLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:to="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7f62-9b18-22ef9a81256d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_MacauGovernmentMember_01a198af-cfbc-7b37-84ff-844067d83427" xlink:href="wynn-20260930.xsd#wynn_MacauGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a198af-cfbc-77a7-bbe6-ac4eee72b7d2" xlink:to="loc_wynn_MacauGovernmentMember_01a198af-cfbc-7b37-84ff-844067d83427" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-70a3-8b19-41f7030eafd3_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-70a3-8b19-41f7030eafd3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7c7d-8a6e-2c464d12c9da" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a198af-cfbc-70a3-8b19-41f7030eafd3" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7c7d-8a6e-2c464d12c9da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7c6c-89c4-3801efbad536" xlink:href="wynn-20260930.xsd#wynn_DCPAMI3FZLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a198af-cfbc-7c7d-8a6e-2c464d12c9da" xlink:to="loc_wynn_DCPAMI3FZLLCMember_01a198af-cfbc-7c6c-89c4-3801efbad536" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7a1b-a5e9-042e01b2929f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7a1b-a5e9-042e01b2929f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7096-b0a7-c048655b9b3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_01a198af-cfbc-7a1b-a5e9-042e01b2929f" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7096-b0a7-c048655b9b3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_01a198af-cfbc-72a3-8cbe-216259e30cbb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_01a198af-cfbc-7096-b0a7-c048655b9b3a" xlink:to="loc_us-gaap_SubsequentEventMember_01a198af-cfbc-72a3-8cbe-216259e30cbb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-7f98-a86a-d0ff13a9e4dd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-7f98-a86a-d0ff13a9e4dd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-71af-9cfe-eb8e78af4bba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_01a198f7-e160-7f98-a86a-d0ff13a9e4dd" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-71af-9cfe-eb8e78af4bba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_01a198f8-2826-7a84-bbad-687dbf4f1c39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_01a198f7-e160-71af-9cfe-eb8e78af4bba" xlink:to="loc_us-gaap_InterestRateContractMember_01a198f8-2826-7a84-bbad-687dbf4f1c39" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-77f2-9b9e-7923e314e7ef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:to="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-77f2-9b9e-7923e314e7ef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_01a198f9-1f7e-77f2-9b9e-7923e314e7ef" xlink:to="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EmiratesInterbankOfferedRateMember_01a198f9-50a4-789e-a23c-d131f3cc10a7" xlink:href="wynn-20260930.xsd#wynn_EmiratesInterbankOfferedRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:to="loc_wynn_EmiratesInterbankOfferedRateMember_01a198f9-50a4-789e-a23c-d131f3cc10a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_01a198f9-9925-7791-8ca8-1eb274f49dd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_01a198f9-1f7e-739a-951c-05285c04a9e9" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember_01a198f9-9925-7791-8ca8-1eb274f49dd3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_01a198af-cfbc-71d7-af96-a7d9c7c02cff" xlink:to="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7989-8a0e-e9e372f6bf32_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:to="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7989-8a0e-e9e372f6bf32_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7a5d-8967-84a145426ccc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitmentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_OtherCommitmentsAxis_01a198fd-462b-7989-8a0e-e9e372f6bf32" xlink:to="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7a5d-8967-84a145426ccc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_MacauGovernmentInvestmentFundCapitalCommitmentsMember_01a198fd-6aec-71ba-ab84-5a1998393b35" xlink:href="wynn-20260930.xsd#wynn_MacauGovernmentInvestmentFundCapitalCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherCommitmentsDomain_01a198fd-462b-7a5d-8967-84a145426ccc" xlink:to="loc_wynn_MacauGovernmentInvestmentFundCapitalCommitmentsMember_01a198fd-6aec-71ba-ab84-5a1998393b35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyContributedCapitalToCommittedCapitalRatio_01a198af-cfbc-7177-99ca-0f238bb0de00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyContributedCapitalToCommittedCapitalRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_InvestmentCompanyContributedCapitalToCommittedCapitalRatio_01a198af-cfbc-7177-99ca-0f238bb0de00" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaymentsForContributedCapital_01a198af-cfbc-7aa7-9902-04f58f9c7f0d" xlink:href="wynn-20260930.xsd#wynn_PaymentsForContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_PaymentsForContributedCapital_01a198af-cfbc-7aa7-9902-04f58f9c7f0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyCommittedCapital_01a198af-cfbc-751f-962f-b3d24e61bab5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyCommittedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_InvestmentCompanyCommittedCapital_01a198af-cfbc-751f-962f-b3d24e61bab5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a198af-cfbc-7bc9-bac4-abcaae25d2bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a198af-cfbc-7bc9-bac4-abcaae25d2bf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableNet_01a198af-cfbc-7ebd-9d33-1884a11c70c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotesReceivableNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_NotesReceivableNet_01a198af-cfbc-7ebd-9d33-1884a11c70c7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_01a198af-cfbc-7005-a8e2-fd0ac840b6ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_EquityMethodInvestments_01a198af-cfbc-7005-a8e2-fd0ac840b6ae" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OperatingLeaseArea_01a198af-cfbc-7385-912f-9191db6f81ef" xlink:href="wynn-20260930.xsd#wynn_OperatingLeaseArea"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_OperatingLeaseArea_01a198af-cfbc-7385-912f-9191db6f81ef" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseTermOfContract_01a198af-cfbc-723a-9ce3-4765adef65d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_LesseeOperatingLeaseTermOfContract_01a198af-cfbc-723a-9ce3-4765adef65d0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_PaymentsToAcquireOperatingLease_01a198af-cfbc-7fc3-a007-da18dbb31971" xlink:href="wynn-20260930.xsd#wynn_PaymentsToAcquireOperatingLease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_PaymentsToAcquireOperatingLease_01a198af-cfbc-7fc3-a007-da18dbb31971" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseExpense_01a198af-cfbc-7382-9030-65cc1cdd4824" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_OperatingLeaseExpense_01a198af-cfbc-7382-9030-65cc1cdd4824" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_DerivativeNotionalAmountPercentageEqualToDebtFaceAmount_01a198f7-74f5-7242-8bdc-7abd053dac86" xlink:href="wynn-20260930.xsd#wynn_DerivativeNotionalAmountPercentageEqualToDebtFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_wynn_DerivativeNotionalAmountPercentageEqualToDebtFaceAmount_01a198f7-74f5-7242-8bdc-7abd053dac86" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeVariableInterestRate_01a198f8-f834-744d-89d8-bb4d0bbd790d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeVariableInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_DerivativeVariableInterestRate_01a198f8-f834-744d-89d8-bb4d0bbd790d" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_01a198fa-0f57-7fc2-a2d0-6acb7dc41ee3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_DerivativeAssets_01a198fa-0f57-7fc2-a2d0-6acb7dc41ee3" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_01a198fa-c762-7329-bc66-028f38c2abdf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_DerivativeLiabilities_01a198fa-c762-7329-bc66-028f38c2abdf" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198fc-032d-75b6-bed8-a3deb302cb75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDerivativeInstrumentsNetPretax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198fc-032d-75b6-bed8-a3deb302cb75" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitment_01a198fd-04bf-7b46-a7c1-2534df0b7e47" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_01a198af-cfbc-72c4-a406-a81390bcd2f9" xlink:to="loc_us-gaap_OtherCommitment_01a198fd-04bf-7b46-a7c1-2534df0b7e47" xlink:type="arc" order="15"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/RetailJointVentureAdditionalinformationDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#RetailJointVentureAdditionalinformationDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/RetailJointVentureAdditionalinformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a198af-cfbc-71bf-aa76-24c932ecf95e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a198af-cfbc-7d64-99bd-4472e661a2ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a198af-cfbc-71bf-aa76-24c932ecf95e" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a198af-cfbc-7d64-99bd-4472e661a2ab" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-7d2f-a8c2-6b6b2a81d554" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a198af-cfbc-7d64-99bd-4472e661a2ab" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-7d2f-a8c2-6b6b2a81d554" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-7d2f-a8c2-6b6b2a81d554_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7d2f-a8c2-6b6b2a81d554" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-7d2f-a8c2-6b6b2a81d554_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-77a0-bb83-c41b7073ddcf" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7d2f-a8c2-6b6b2a81d554" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-77a0-bb83-c41b7073ddcf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_RetailJointVentureMember_01a198af-cfbc-7818-b6ef-9293940e19b4" xlink:href="wynn-20260930.xsd#wynn_RetailJointVentureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-77a0-bb83-c41b7073ddcf" xlink:to="loc_wynn_RetailJointVentureMember_01a198af-cfbc-7818-b6ef-9293940e19b4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7c14-9b15-9d6b5cd4115a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a198af-cfbc-7d64-99bd-4472e661a2ab" xlink:to="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7c14-9b15-9d6b5cd4115a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7c14-9b15-9d6b5cd4115a_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7c14-9b15-9d6b5cd4115a" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7c14-9b15-9d6b5cd4115a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7779-87b1-22350b42a696" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7c14-9b15-9d6b5cd4115a" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7779-87b1-22350b42a696" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetailMember_01a198af-cfbc-73ac-a203-1a18429b51f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetailMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7779-87b1-22350b42a696" xlink:to="loc_us-gaap_RetailMember_01a198af-cfbc-73ac-a203-1a18429b51f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_01a198af-cfbc-78d2-8f92-f369a5856199" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a198af-cfbc-71bf-aa76-24c932ecf95e" xlink:to="loc_us-gaap_Assets_01a198af-cfbc-78d2-8f92-f369a5856199" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_01a198af-cfbc-7a6c-859a-c29687e50f33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a198af-cfbc-71bf-aa76-24c932ecf95e" xlink:to="loc_us-gaap_Liabilities_01a198af-cfbc-7a6c-859a-c29687e50f33" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_01a198af-cfbc-7812-80ae-aa064878a8a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a198af-cfbc-71bf-aa76-24c932ecf95e" xlink:to="loc_us-gaap_LongTermDebt_01a198af-cfbc-7812-80ae-aa064878a8a5" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/SegmentInformationSummaryofResultsofOperationsbySegmentDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#SegmentInformationSummaryofResultsofOperationsbySegmentDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/SegmentInformationSummaryofResultsofOperationsbySegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7a93-8bb0-616aef3b2e12" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7a93-8bb0-616aef3b2e12" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7d6a-b0e7-6257bf9f588d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7a93-8bb0-616aef3b2e12" xlink:to="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7d6a-b0e7-6257bf9f588d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7d6a-b0e7-6257bf9f588d_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7d6a-b0e7-6257bf9f588d" xlink:to="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7d6a-b0e7-6257bf9f588d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-792e-9236-ef35111db746" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7d6a-b0e7-6257bf9f588d" xlink:to="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-792e-9236-ef35111db746" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a198af-cfbc-713d-b2f4-04647a29c701" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-792e-9236-ef35111db746" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a198af-cfbc-713d-b2f4-04647a29c701" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-766d-953b-d8cce8284407" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7a93-8bb0-616aef3b2e12" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-766d-953b-d8cce8284407" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-766d-953b-d8cce8284407_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-766d-953b-d8cce8284407" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-766d-953b-d8cce8284407_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-7e85-adfd-45bb3e8ac837" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-766d-953b-d8cce8284407" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-7e85-adfd-45bb3e8ac837" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnPalaceMember_01a198af-cfbc-724c-bc26-edb1043fa6ff" xlink:href="wynn-20260930.xsd#wynn_WynnPalaceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-7e85-adfd-45bb3e8ac837" xlink:to="loc_wynn_WynnPalaceMember_01a198af-cfbc-724c-bc26-edb1043fa6ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauMember_01a198af-cfbc-7ac0-af83-5ecafc901417" xlink:href="wynn-20260930.xsd#wynn_WynnMacauMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-7e85-adfd-45bb3e8ac837" xlink:to="loc_wynn_WynnMacauMember_01a198af-cfbc-7ac0-af83-5ecafc901417" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-78a9-ba26-ec925bc062d1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7a93-8bb0-616aef3b2e12" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-78a9-ba26-ec925bc062d1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a198af-cfbc-78a9-ba26-ec925bc062d1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-78a9-ba26-ec925bc062d1" xlink:to="loc_us-gaap_SegmentDomain_01a198af-cfbc-78a9-ba26-ec925bc062d1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a198af-cfbc-73c4-91a4-cbdece39f960" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-78a9-ba26-ec925bc062d1" xlink:to="loc_us-gaap_SegmentDomain_01a198af-cfbc-73c4-91a4-cbdece39f960" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_MacauOperationsMember_01a198af-cfbc-79a8-a55b-0a0e82c42508" xlink:href="wynn-20260930.xsd#wynn_MacauOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-73c4-91a4-cbdece39f960" xlink:to="loc_wynn_MacauOperationsMember_01a198af-cfbc-79a8-a55b-0a0e82c42508" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_LasVegasOperationsMember_01a198af-cfbc-7e23-a2b5-1a325e210803" xlink:href="wynn-20260930.xsd#wynn_LasVegasOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-73c4-91a4-cbdece39f960" xlink:to="loc_wynn_LasVegasOperationsMember_01a198af-cfbc-7e23-a2b5-1a325e210803" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EncoreBostonHarborMember_01a198af-cfbc-730b-9092-217dadce42e9" xlink:href="wynn-20260930.xsd#wynn_EncoreBostonHarborMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-73c4-91a4-cbdece39f960" xlink:to="loc_wynn_EncoreBostonHarborMember_01a198af-cfbc-730b-9092-217dadce42e9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7a2e-aec8-5ddaef8bdbef" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7a93-8bb0-616aef3b2e12" xlink:to="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7a2e-aec8-5ddaef8bdbef" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7a2e-aec8-5ddaef8bdbef_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7a2e-aec8-5ddaef8bdbef" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7a2e-aec8-5ddaef8bdbef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7266-b49e-db8c0077c8e4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_01a198af-cfbc-7a2e-aec8-5ddaef8bdbef" xlink:to="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7266-b49e-db8c0077c8e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CasinoMember_01a198af-cfbc-7566-95fd-bf53c6266211" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CasinoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7266-b49e-db8c0077c8e4" xlink:to="loc_us-gaap_CasinoMember_01a198af-cfbc-7566-95fd-bf53c6266211" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OccupancyMember_01a198af-cfbc-7606-bdb5-cfc1a1493a70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OccupancyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7266-b49e-db8c0077c8e4" xlink:to="loc_us-gaap_OccupancyMember_01a198af-cfbc-7606-bdb5-cfc1a1493a70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FoodAndBeverageMember_01a198af-cfbc-7399-999e-9b28aaeae879" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FoodAndBeverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7266-b49e-db8c0077c8e4" xlink:to="loc_us-gaap_FoodAndBeverageMember_01a198af-cfbc-7399-999e-9b28aaeae879" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EntertainmentRetailAndOtherMember_01a198af-cfbc-7eda-863e-c8bff4120dd8" xlink:href="wynn-20260930.xsd#wynn_EntertainmentRetailAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_01a198af-cfbc-7266-b49e-db8c0077c8e4" xlink:to="loc_wynn_EntertainmentRetailAndOtherMember_01a198af-cfbc-7eda-863e-c8bff4120dd8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_NumberOfReportableSegmentsNotDisclosedFlag_01a198af-cfbc-7167-9570-34b3f7fae7b2" xlink:href="wynn-20260930.xsd#wynn_NumberOfReportableSegmentsNotDisclosedFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_wynn_NumberOfReportableSegmentsNotDisclosedFlag_01a198af-cfbc-7167-9570-34b3f7fae7b2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_01a198af-cfbc-74e8-8cbb-e813eb0999d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_01a198af-cfbc-74e8-8cbb-e813eb0999d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_01a198af-cfbc-7dfb-878d-ee4a354faaa1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_01a198af-cfbc-7dfb-878d-ee4a354faaa1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_GamingTaxExpensesIncludingTableAndSlotLicenseFees_01a198af-cfbc-7700-985b-1d2f168da2a0" xlink:href="wynn-20260930.xsd#wynn_GamingTaxExpensesIncludingTableAndSlotLicenseFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_wynn_GamingTaxExpensesIncludingTableAndSlotLicenseFees_01a198af-cfbc-7700-985b-1d2f168da2a0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_AdjustedPropertyEbitdar_01a198af-cfbc-700f-8fce-968678e9651f" xlink:href="wynn-20260930.xsd#wynn_AdjustedPropertyEbitdar"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_wynn_AdjustedPropertyEbitdar_01a198af-cfbc-700f-8fce-968678e9651f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:href="wynn-20260930.xsd#wynn_OtherOperatingCostsAndExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreOpeningCosts_01a198af-cfbc-7eff-b3b1-15aaa0f6ceb8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreOpeningCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:to="loc_us-gaap_PreOpeningCosts_01a198af-cfbc-7eff-b3b1-15aaa0f6ceb8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_01a198af-cfbc-76df-9684-210df59c56a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:to="loc_us-gaap_DepreciationAndAmortization_01a198af-cfbc-76df-9684-210df59c56a4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_ProjectAbandonmentCosts_01a198af-cfbc-7743-9a33-d817db597f49" xlink:href="wynn-20260930.xsd#wynn_ProjectAbandonmentCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:to="loc_wynn_ProjectAbandonmentCosts_01a198af-cfbc-7743-9a33-d817db597f49" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_CorporateExpensesAndOther_01a198af-cfbc-7d52-bf16-6139dd62e7da" xlink:href="wynn-20260930.xsd#wynn_CorporateExpensesAndOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:to="loc_wynn_CorporateExpensesAndOther_01a198af-cfbc-7d52-bf16-6139dd62e7da" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_01a198af-cfbc-778c-a5ee-c83969e3dea0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:to="loc_us-gaap_ShareBasedCompensation_01a198af-cfbc-778c-a5ee-c83969e3dea0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OperatingLeaseTripleNetCost_01a198af-cfbc-7dae-aa92-0dc95ebe8530" xlink:href="wynn-20260930.xsd#wynn_OperatingLeaseTripleNetCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_wynn_OtherOperatingCostsAndExpensesAbstract_01a198af-cfbc-7ba4-9945-4ac42c16036c" xlink:to="loc_wynn_OperatingLeaseTripleNetCost_01a198af-cfbc-7dae-aa92-0dc95ebe8530" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_01a198af-cfbc-769e-b840-ba6f5c8316bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_OperatingIncomeLoss_01a198af-cfbc-769e-b840-ba6f5c8316bc" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpenseAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInterest_01a198af-cfbc-7b69-a02a-a68a3afcafd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:to="loc_us-gaap_InvestmentIncomeInterest_01a198af-cfbc-7b69-a02a-a68a3afcafd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_01a198af-cfbc-738c-9a45-d4bab3fd55d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:to="loc_us-gaap_InterestExpenseNonoperating_01a198af-cfbc-738c-9a45-d4bab3fd55d8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198af-cfbc-72ad-96f5-33adb7dd1ec7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDerivativeInstrumentsNetPretax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:to="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_01a198af-cfbc-72ad-96f5-33adb7dd1ec7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a198af-cfbc-7241-b8bb-1ec798836379" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a198af-cfbc-7241-b8bb-1ec798836379" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_01a198af-cfbc-7923-872e-b359ef15c737" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_01a198af-cfbc-7923-872e-b359ef15c737" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_01a198af-cfbc-750c-89ff-2cfbb9cabbf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_01a198af-cfbc-7307-81ec-d5e9518db2f5" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_01a198af-cfbc-750c-89ff-2cfbb9cabbf0" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_01a198af-cfbc-742f-9e04-802a34c6319c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_01a198af-cfbc-742f-9e04-802a34c6319c" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_01a198af-cfbc-7bae-bd14-80708b0a457d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_01a198af-cfbc-7bae-bd14-80708b0a457d" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_01a198af-cfbc-71ed-bc2f-412aa45dc9ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_ProfitLoss_01a198af-cfbc-71ed-bc2f-412aa45dc9ae" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_01a198af-cfbc-7e84-8cf0-a3a57a1b59c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_01a198af-cfbc-7e84-8cf0-a3a57a1b59c2" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_01a198af-cfbc-71ce-94fc-0cea84527d0f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-74a6-b214-51c765124de7" xlink:to="loc_us-gaap_NetIncomeLoss_01a198af-cfbc-71ce-94fc-0cea84527d0f" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/SegmentInformationScheduleofCapitalExpendituresDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#SegmentInformationScheduleofCapitalExpendituresDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/SegmentInformationScheduleofCapitalExpendituresDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-7d3c-a7f9-cb64423aa870" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-703c-a93b-519efe867859" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-7d3c-a7f9-cb64423aa870" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-703c-a93b-519efe867859" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a198af-cfbc-7b9a-ac13-8771f6ae63b0" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-703c-a93b-519efe867859" xlink:to="loc_dei_LegalEntityAxis_01a198af-cfbc-7b9a-ac13-8771f6ae63b0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-7b9a-ac13-8771f6ae63b0_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7b9a-ac13-8771f6ae63b0" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-7b9a-ac13-8771f6ae63b0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a198af-cfbc-768f-ae57-a4b34a8d03e7" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a198af-cfbc-7b9a-ac13-8771f6ae63b0" xlink:to="loc_dei_EntityDomain_01a198af-cfbc-768f-ae57-a4b34a8d03e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnPalaceMember_01a198af-cfbc-7678-9d87-8779f7562dcf" xlink:href="wynn-20260930.xsd#wynn_WynnPalaceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-768f-ae57-a4b34a8d03e7" xlink:to="loc_wynn_WynnPalaceMember_01a198af-cfbc-7678-9d87-8779f7562dcf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauMember_01a198af-cfbc-74af-a863-17deb5df2bd1" xlink:href="wynn-20260930.xsd#wynn_WynnMacauMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a198af-cfbc-768f-ae57-a4b34a8d03e7" xlink:to="loc_wynn_WynnMacauMember_01a198af-cfbc-74af-a863-17deb5df2bd1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7ced-99e9-d88ef5a3987b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-703c-a93b-519efe867859" xlink:to="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7ced-99e9-d88ef5a3987b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7ced-99e9-d88ef5a3987b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7ced-99e9-d88ef5a3987b" xlink:to="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7ced-99e9-d88ef5a3987b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7518-913a-8a3713823afb" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7ced-99e9-d88ef5a3987b" xlink:to="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7518-913a-8a3713823afb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a198af-cfbc-79af-a26e-1e98e97cd896" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7518-913a-8a3713823afb" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a198af-cfbc-79af-a26e-1e98e97cd896" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7797-b640-37ea02e499fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-703c-a93b-519efe867859" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7797-b640-37ea02e499fb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a198af-cfbc-7797-b640-37ea02e499fb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7797-b640-37ea02e499fb" xlink:to="loc_us-gaap_SegmentDomain_01a198af-cfbc-7797-b640-37ea02e499fb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a198af-cfbc-7f57-89a5-3898dd427519" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7797-b640-37ea02e499fb" xlink:to="loc_us-gaap_SegmentDomain_01a198af-cfbc-7f57-89a5-3898dd427519" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_MacauOperationsMember_01a198af-cfbc-7c51-bdd0-fc1d8cdc1a58" xlink:href="wynn-20260930.xsd#wynn_MacauOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7f57-89a5-3898dd427519" xlink:to="loc_wynn_MacauOperationsMember_01a198af-cfbc-7c51-bdd0-fc1d8cdc1a58" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_LasVegasOperationsMember_01a198af-cfbc-7967-bece-db28b667ef52" xlink:href="wynn-20260930.xsd#wynn_LasVegasOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7f57-89a5-3898dd427519" xlink:to="loc_wynn_LasVegasOperationsMember_01a198af-cfbc-7967-bece-db28b667ef52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EncoreBostonHarborMember_01a198af-cfbc-71a8-bbe6-d8337d064572" xlink:href="wynn-20260930.xsd#wynn_EncoreBostonHarborMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7f57-89a5-3898dd427519" xlink:to="loc_wynn_EncoreBostonHarborMember_01a198af-cfbc-71a8-bbe6-d8337d064572" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_01a198af-cfbc-76b7-ac1e-34f19831b93b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7f57-89a5-3898dd427519" xlink:to="loc_us-gaap_CorporateAndOtherMember_01a198af-cfbc-76b7-ac1e-34f19831b93b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentExpenditureAdditionToLongLivedAssets_01a198af-cfbc-7584-a991-f5891086f47d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentExpenditureAdditionToLongLivedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-7d3c-a7f9-cb64423aa870" xlink:to="loc_us-gaap_SegmentExpenditureAdditionToLongLivedAssets_01a198af-cfbc-7584-a991-f5891086f47d" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.wynnresorts.com/role/SegmentInformationSummaryofAssetsbySegmentDetails" xlink:type="simple" xlink:href="wynn-20260930.xsd#SegmentInformationSummaryofAssetsbySegmentDetails"/>
  <link:definitionLink xlink:role="http://www.wynnresorts.com/role/SegmentInformationSummaryofAssetsbySegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-7691-8a25-a41e4711cfb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7ba5-b87c-251e07797a3d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-7691-8a25-a41e4711cfb4" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7ba5-b87c-251e07797a3d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7484-ab0c-41edb7c0fa2d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7ba5-b87c-251e07797a3d" xlink:to="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7484-ab0c-41edb7c0fa2d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7484-ab0c-41edb7c0fa2d_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7484-ab0c-41edb7c0fa2d" xlink:to="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-7484-ab0c-41edb7c0fa2d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-759c-b80a-de355aebbfca" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_01a198af-cfbc-7484-ab0c-41edb7c0fa2d" xlink:to="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-759c-b80a-de355aebbfca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a198af-cfbc-7d83-a206-94fdb0233045" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_01a198af-cfbc-759c-b80a-de355aebbfca" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a198af-cfbc-7d83-a206-94fdb0233045" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7c59-b02c-82e44578df26" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7ba5-b87c-251e07797a3d" xlink:to="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7c59-b02c-82e44578df26" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-7c59-b02c-82e44578df26_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7c59-b02c-82e44578df26" xlink:to="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-7c59-b02c-82e44578df26_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-71d0-9103-f99c4296da08" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_01a198af-cfbc-7c59-b02c-82e44578df26" xlink:to="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-71d0-9103-f99c4296da08" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_MO_01a198af-cfbc-7997-bcfa-99ad517d42bd" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_MO"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_01a198af-cfbc-71d0-9103-f99c4296da08" xlink:to="loc_country_MO_01a198af-cfbc-7997-bcfa-99ad517d42bd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7c6c-bbbc-fad532eedfd5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a198af-cfbc-7ba5-b87c-251e07797a3d" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7c6c-bbbc-fad532eedfd5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a198af-cfbc-7c6c-bbbc-fad532eedfd5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7c6c-bbbc-fad532eedfd5" xlink:to="loc_us-gaap_SegmentDomain_01a198af-cfbc-7c6c-bbbc-fad532eedfd5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_01a198af-cfbc-7c6c-bbbc-fad532eedfd5" xlink:to="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnPalaceMember_01a198af-cfbc-73a3-816a-385183a887af" xlink:href="wynn-20260930.xsd#wynn_WynnPalaceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:to="loc_wynn_WynnPalaceMember_01a198af-cfbc-73a3-816a-385183a887af" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnMacauMember_01a198af-cfbc-7f45-85c2-b7de513a43a9" xlink:href="wynn-20260930.xsd#wynn_WynnMacauMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:to="loc_wynn_WynnMacauMember_01a198af-cfbc-7f45-85c2-b7de513a43a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_OtherMacauMember_01a198af-cfbc-73b1-8c11-4d916c716143" xlink:href="wynn-20260930.xsd#wynn_OtherMacauMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:to="loc_wynn_OtherMacauMember_01a198af-cfbc-73b1-8c11-4d916c716143" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_MacauOperationsMember_01a198af-cfbc-77b3-a4dd-df08a06b37e4" xlink:href="wynn-20260930.xsd#wynn_MacauOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:to="loc_wynn_MacauOperationsMember_01a198af-cfbc-77b3-a4dd-df08a06b37e4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_WynnLasVegasMember_01a198af-cfbc-7b4a-8329-2704dafedd57" xlink:href="wynn-20260930.xsd#wynn_WynnLasVegasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:to="loc_wynn_WynnLasVegasMember_01a198af-cfbc-7b4a-8329-2704dafedd57" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_wynn_EncoreBostonHarborMember_01a198af-cfbc-785a-975c-927b432aa265" xlink:href="wynn-20260930.xsd#wynn_EncoreBostonHarborMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:to="loc_wynn_EncoreBostonHarborMember_01a198af-cfbc-785a-975c-927b432aa265" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateAndOtherMember_01a198af-cfbc-7497-a91d-e7b0315b95c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateAndOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a198af-cfbc-7234-bb36-daafe5c9afe3" xlink:to="loc_us-gaap_CorporateAndOtherMember_01a198af-cfbc-7497-a91d-e7b0315b95c5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_01a198af-cfbc-75b7-8bc1-65f3f6ca33e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a198af-cfbc-7691-8a25-a41e4711cfb4" xlink:to="loc_us-gaap_Assets_01a198af-cfbc-75b7-8bc1-65f3f6ca33e0" xlink:type="arc" order="0"/>
  </link:definitionLink>
</link:linkbase>
