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bats in one's belfry, have

Idioms  

  1. Be crazy or at least very eccentric, as in Sally thought her aunt's belief in ghosts indicated she had bats in her belfry. This term in effect likens the bat's seemingly erratic flight in the dark to ideas flying around in a person's head. [Early 1900s]

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.

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