bats in one's belfry, to have

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.
See also: bats, belfry, have
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.
See also: bats, belfry, have
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

bats in one's belfry, to have

To be slightly crazy or quite eccentric. The term alludes to the bat’s seemingly erratic flight in the dark, which is transferred to thoughts flying about in the head. In reality, the bat has a sophisticated sonar system whose nature came to light only recently. In flight it keeps up a constant twittering noise that bounces back from solid objects in its path. This echo enables the animal to avoid actually bumping into obstacles. Nevertheless, bats have long been associated with craziness. See also blind as a bat.
See also: bats, have, to
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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