diff --git a/sys/src/cmd/5a/lex.c b/sys/src/cmd/5a/lex.c
index e052ce284..3ef90982d 100644
--- a/sys/src/cmd/5a/lex.c
+++ b/sys/src/cmd/5a/lex.c
@@ -283,6 +283,7 @@ struct
 	"SLL",		LTYPE1,	ASLL,
 	"SRL",		LTYPE1,	ASRL,
 	"SRA",		LTYPE1,	ASRA,
+	"ROR",		LTYPE1, AROR,
 
 	"MUL",		LTYPE1, AMUL,
 	"MULA",		LTYPEN, AMULA,