diff --git a/keysymdef.h b/keysymdef.h
index b3ade4d..14d6e07 100644
--- a/keysymdef.h
+++ b/keysymdef.h
@@ -2034,6 +2034,11 @@ SOFTWARE.
 #define XK_Uhorn                      0x10001af  /* U+01AF LATIN CAPITAL LETTER U WITH HORN */
 #define XK_uhorn                      0x10001b0  /* U+01B0 LATIN SMALL LETTER U WITH HORN */
 
+#define XK_combining_tilde            0x1000303  /* U+0303 COMBINING TILDE */
+#define XK_combining_grave            0x1000300  /* U+0300 COMBINING GRAVE ACCENT */
+#define XK_combining_acute            0x1000301  /* U+0301 COMBINING ACUTE ACCENT */
+#define XK_combining_hook             0x1000309  /* U+0309 COMBINING HOOK ABOVE */
+#define XK_combining_belowdot         0x1000323  /* U+0323 COMBINING DOT BELOW */
 #endif /* XK_VIETNAMESE */
 
 #ifdef XK_CURRENCY