adjective, daf·fi·er, daf·fi·est. Informal.
- silly; weak-minded; crazy.
adjective daffier or daffiest
- informal another word for daft (def. 1), daft (def. 2)
1884, perhaps from daft (adj.), or from obsolete daffe “halfwit” (cf. 15c. daffish), of unknown origin. With -y (2). Related: Daffily; daffiness.