Green’s Dictionary of Slang

(Irish) an impertinent, conceited youngster.

1922		Joyce Ulysses 346: Miss punt little Edy’s countenance fell to no slight extent and Gerty could see by her looking as black as thunder that she was simply in a towering rage though she hid it, the little kinatt.
1979		M. O’Beirne Mister, A Dublin Childhood 82: ‘Well after that,’ my mother said, meaning there were no wonders left. ‘The clever kinat.’ .
1985		M. Johnston Around the Banks of Pimlico 115: That bloody canat is never around when he’s wanted .