a bee in bonnet

a bee in (one's) bonnet

An obsession, often with something that is strange or a source of agitation. Ever since the blizzard last year, Dad has had a bee in his bonnet about moving to a warmer climate. It seems that Mike still has a bee in his bonnet over the criticism he got in the staff meeting.
See also: bee, bonnet
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

a bee in (one's) bonnet

1. An impulse to do something; a notion.
2. An obsession.
See also: bee, bonnet
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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