diff --git a/sys/posix/include/sys/socket.h b/sys/posix/include/sys/socket.h
index d8207ccf3f..8bac3ce558 100644
--- a/sys/posix/include/sys/socket.h
+++ b/sys/posix/include/sys/socket.h
@@ -36,9 +36,6 @@
   sa_family_t sa_prefix##family
 
 #define __SOCKADDR_COMMON_SIZE  (sizeof (unsigned short int))
-#ifdef __MACH__
-#define AF_LINK (18)    /* Link layer interface */
-#endif
 #endif
 
 #include <stdlib.h>