Green’s Dictionary of Slang

silly, stupid.

1898		(con. 1875) F.T. Bullen Cruise of the ‘Cachalot’ 39: He was severely handicapped by his crew [...] two of them were now temporarily incapable of either good or harm. They had gone quite ‘batchy’ with fright.
1925		(con. WWI) Fraser & Gibbons Soldier and Sailor Words 19: Batchy: Mad. Silly.
1929		N. Jacob Man Who Found Himself (1952) 94: I shall sound like someone who’s a bit batchy.
1935		Thieves Slang ms list from District Police Training Centre, Ryton-on-Dunsmore, Warwicks 5: Gone batchy: Insane.
1935		Portsmouth Eve. News 19 Feb. 12/2: Mr Cassels, opening foer the defence, submitted that the prisoner was insane [...] ‘In the Service [...] he was known as Batchy Brigstock’.
1936		J. Curtis Gilt Kid 229: He was not going to be quite dopey and keep cuttings like some batchy bastards did.
1958		A. Sillitoe Sat. Night and Sun. Morning 44: He must know: no man is that batchy.
1993		(con. 1945) S. McAughtry Touch and Go 93: John’s liable to go batchy for ever.
2003		(con. 1933) W. Woodruff Beyond Nab End 66: The Tinkers thought I’d gone ‘batchy’.