diff --git a/Modules/Platform/Windows-MSVC.cmake b/Modules/Platform/Windows-MSVC.cmake
index 5809379f00..a897e50d46 100644
--- a/Modules/Platform/Windows-MSVC.cmake
+++ b/Modules/Platform/Windows-MSVC.cmake
@@ -240,7 +240,7 @@ elseif(CMAKE_SYSTEM_NAME STREQUAL "WindowsKernelModeDriver")
 else()
   set(_PLATFORM_DEFINES "/DWIN32")
   if((_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM64EC") OR (_MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM64EC"))
-    set(_PLATFORM_DEFINES "${_PLATFORM_DEFINES} /D_AMD64_ /DAMD64 /D_ARM64EC_ /DARM64EC")
+    set(_PLATFORM_DEFINES "${_PLATFORM_DEFINES} /D_AMD64_ /D_ARM64EC_")
   endif()
   if(_MSVC_C_ARCHITECTURE_FAMILY STREQUAL "ARM" OR _MSVC_CXX_ARCHITECTURE_FAMILY STREQUAL "ARM")
     set(CMAKE_C_STANDARD_LIBRARIES_INIT "kernel32.lib user32.lib")