diff --git a/win32ss/include/ntuser.h b/win32ss/include/ntuser.h
index d92796dd3d9..9485f574487 100644
--- a/win32ss/include/ntuser.h
+++ b/win32ss/include/ntuser.h
@@ -3499,7 +3499,7 @@ NTAPI
 NtUserWaitForInputIdle(
     IN HANDLE hProcess,
     IN DWORD dwMilliseconds,
-    IN BOOL Unknown2); /* Always FALSE */
+    IN BOOL bSharedWow); /* Always FALSE */
 
 DWORD
 NTAPI