Green’s Dictionary of Slang

twatty adj.

stupid.

1978		P. Theroux Picture Palace 314: Doris kneeling, twatty.
2000		N. Griffiths Grits 26: Ee’s only about my age and, aftuh first impressions, doesunt rirly look too twatty.
2007		R. Milward Apples (2023) 99: Mr Barley was in a tight white vest and twatty biker trousers.