diff --git a/src/runtime/defs_netbsd.go b/src/runtime/defs_netbsd.go
index ec4d796bd32..a48de2ae817 100644
--- a/src/runtime/defs_netbsd.go
+++ b/src/runtime/defs_netbsd.go
@@ -45,9 +45,10 @@ const (
 	PROT_WRITE = C.PROT_WRITE
 	PROT_EXEC  = C.PROT_EXEC
 
-	MAP_ANON    = C.MAP_ANON
-	MAP_PRIVATE = C.MAP_PRIVATE
-	MAP_FIXED   = C.MAP_FIXED
+	MAP_ANON      = C.MAP_ANON
+	MAP_ANONYMOUS = C.MAP_ANON
+	MAP_PRIVATE   = C.MAP_PRIVATE
+	MAP_FIXED     = C.MAP_FIXED
 
 	MADV_DONTNEED = C.MADV_DONTNEED
 	MADV_FREE     = C.MADV_FREE