diff --git a/lisp/server.el b/lisp/server.el
index beb065ef437..f03c802bb77 100644
--- a/lisp/server.el
+++ b/lisp/server.el
@@ -311,7 +311,8 @@ client \"editors\" can send your editing commands to this Emacs job.
 To use the server, set up the program `emacsclient' in the
 Emacs distribution as your standard \"editor\".
 
-Prefix arg means just kill any existing server communications subprocess."
+Optional argument LEAVE-DEAD (interactively, a prefix arg) means just
+kill any existing server communications subprocess."
   (interactive "P")
   (when server-process
     ;; kill it dead!