From Longman Dictionary of Contemporary Englishbattybat‧ty /ˈbæti/ adjective CRAZYslightly crazy, but not in an unpleasant or frightening way SYN nutty
Examples from the Corpus
batty• Wilkens delivers a show-stopping performance as the batty Madame Arcati.• The man is 90 % batty, with flashes of astuteness.Origin batty (1900-2000) → BAT17 