diff --git a/include/wx/defs.h b/include/wx/defs.h
index cc0edcaa38..e1b625bfe4 100644
--- a/include/wx/defs.h
+++ b/include/wx/defs.h
@@ -2097,6 +2097,7 @@ DECLARE_WXCOCOA_OBJC_CLASS(NSTableView);
 DECLARE_WXCOCOA_OBJC_CLASS(NSTextContainer);
 DECLARE_WXCOCOA_OBJC_CLASS(NSTextField);
 DECLARE_WXCOCOA_OBJC_CLASS(NSTextStorage);
+DECLARE_WXCOCOA_OBJC_CLASS(NSThread);
 DECLARE_WXCOCOA_OBJC_CLASS(NSWindow);
 DECLARE_WXCOCOA_OBJC_CLASS(NSView);
 typedef WX_NSView WXWidget; // wxWindows BASE definition