-kē, -ki adjective
or smart-aleck also smart-alec
: like, typical of, or being a smart aleck : marked by cockiness and conceit : concerned with or striving for smartness and cleverness for their own sake or at the expense of seriousness and responsibility
had never talked that way to the smart-aleck kid before — J.H.Reese
the smart-aleck way you were talking — Alexander Saxton
dismayingly intelligent and a shade smart-alecky — Jean Stafford
five smart-alecky collegians who conspired to rob the till — Bennett Cerf