diff --git a/include/wx/platform.h b/include/wx/platform.h
index 2f65117d4c..43feae73fe 100644
--- a/include/wx/platform.h
+++ b/include/wx/platform.h
@@ -32,6 +32,9 @@
 #    ifndef MAC_OS_X_VERSION_10_8
 #       define MAC_OS_X_VERSION_10_8 1080
 #    endif
+#    ifndef MAC_OS_X_VERSION_10_9
+#       define MAC_OS_X_VERSION_10_9 1090
+#    endif
 #    include "wx/osx/config_xcode.h"
 #    ifndef __WXOSX__
 #        define __WXOSX__ 1
@@ -527,6 +530,9 @@
 #        ifndef MAC_OS_X_VERSION_10_8
 #           define MAC_OS_X_VERSION_10_8 1080
 #        endif
+#        ifndef MAC_OS_X_VERSION_10_9
+#           define MAC_OS_X_VERSION_10_9 1090
+#        endif
 #    else
 #        error "only mach-o configurations are supported"
 #    endif