have a screw loose

Idioms  

1. Be mentally unstable or eccentric, as in Anyone who approves that purchase must have a screw loose. This term likens a mental weakness to a machine in which a part is not securely fastened. An antonym is have one's head screwed on right; for example, She's very capable; she has her head screwed on right. [Slang; early 1800s]

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Example Sentences

“Everyone in speedskating recognizes that Eric Heiden is the greatest speedskater who ever lived. Even saying, ‘Yeah, we should try that,’ that’s like saying, ‘Do you have a screw loose or something?’

From Washington Times

“You are either incompetent or for some reason you have a screw loose and you want to have open borders.”

From Washington Times

Wlodzimierz Lipa, a 71-year-old pensioner who got his second Pfizer shot last week in Walbrzych, said that people attacking the mayor as a Nazi “have a screw loose.”

From New York Times

“He said, ‘You kind of have to have a screw loose to do this,’” Wood said.

From Washington Times

“I know he has had some tough games and moments but if you don’t like Philip Rivers as your quarterback you have a screw loose if you ask me.”

From Washington Times