diff --git a/sys/sys/socket.h b/sys/sys/socket.h
index 6efdaee6b3ff..ae8f9709a9cc 100644
--- a/sys/sys/socket.h
+++ b/sys/sys/socket.h
@@ -394,7 +394,7 @@ struct msghdr {
 #define	MSG_DONTWAIT	0x80		/* this message should be nonblocking */
 #define	MSG_EOF		0x100		/* data completes connection */
 #define	MSG_NBIO	0x4000		/* FIONBIO mode, used by fifofs */
-#define MSG_COMPAT      0x8000		/* used in sendit() */
+#define	MSG_COMPAT      0x8000		/* used in sendit() */
 #endif
 
 /*