diff --git a/src/or/routerparse.c b/src/or/routerparse.c
index 0aae0aa94..33c68d74b 100644
--- a/src/or/routerparse.c
+++ b/src/or/routerparse.c
@@ -1262,7 +1262,7 @@ dump_distinct_digest_count(int severity)
* s through end into the signed_descriptor_body of the resulting
* routerinfo_t.
*
- * If end is NULL, s must be properly NULL-terminated.
+ * If end is NULL, s must be properly NUL-terminated.
*
* If allow_annotations, it's okay to encounter annotations in s
* before the router; if it's false, reject the router if it's annotated. If