diff --git a/lisp/delsel.el b/lisp/delsel.el
index d5f4736fddb..8cb7adeaa3f 100644
--- a/lisp/delsel.el
+++ b/lisp/delsel.el
@@ -70,9 +70,12 @@ Value must be the register (key) to use.")
 ;;;###autoload
 (define-minor-mode delete-selection-mode
   "Toggle Delete Selection mode.
-With a prefix argument ARG, enable Delete Selection mode if ARG
-is positive, and disable it otherwise.  If called from Lisp,
-enable the mode if ARG is omitted or nil.
+Interactively, with a prefix argument, enable
+Delete Selection mode if the prefix argument is positive,
+and disable it otherwise.  If called from Lisp, toggle
+the mode if ARG is `toggle', disable the mode if ARG is
+a non-positive integer, and enable the mode otherwise
+\(including if ARG is omitted or nil or a positive integer).
 
 When Delete Selection mode is enabled, typed text replaces the selection
 if the selection is active.  Otherwise, typed text is just inserted at