have bats in one's belfry
Definition from Wiktionary, the free dictionary
1899, from tendency of bats to fly around erratically, with “belfry” indicating “head, mind”.
- (idiomatic, intransitive) To be crazy or eccentric.
- Anyone declaring himself Emperor of San Francisco probably had bats in his belfry.
1900, Mary Etta Stickney, Brown of Lost River, page 254:
- You would certainly take the prize for bats in the belfry!--flying off on a wild-goose chase across a country where even the geese need a compass to keep to the course.
- See also Wikisaurus:insane
To be crazy or eccentric