diff --git a/lisp/textmodes/ispell.el b/lisp/textmodes/ispell.el
index 27a60c376c6..9aad5671152 100644
--- a/lisp/textmodes/ispell.el
+++ b/lisp/textmodes/ispell.el
@@ -250,16 +250,14 @@ Always stores Fcc copy of message when nil."
 Should probably be \"-Ei\"."
   :type 'string)
 
-(defcustom ispell-look-command
-  (cond ((file-exists-p "/bin/look") "/bin/look")
-	((file-exists-p "/usr/local/bin/look") "/usr/local/bin/look")
-	((file-exists-p "/usr/bin/look") "/usr/bin/look")
-	(t "look"))
+(defcustom ispell-look-command (executable-find "look")
   "Name of the look command for search processes.
 This must be an absolute file name."
-  :type 'file)
+  :type 'file
+  :version "28.1")
 
-(defcustom ispell-look-p (file-exists-p ispell-look-command)
+(defcustom ispell-look-p (and ispell-look-command
+                              (file-exists-p ispell-look-command))
   "Non-nil means use `look' rather than `grep'.
 Default is based on whether `look' seems to be available."
   :type 'boolean)