have bats in one’s belfry
have bats in (one's) belfry
To be crazy; to act, think, or behave in a foolish or nonsensical manner. Tommy has bats in his belfry if he thinks he can convince our mother to let him get a tattoo for his birthday. There's an old lady who stands on the corner yelling at strangers all day. I think she might have bats in her belfry.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
have bats in one’s belfry(...ˈbɛlfri)
tv. to be crazy. (see also bats. Have got can replace have.) Pay no attention to her. She has bats in her belfry.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.