screw loose

/skruː lus/
adjective
  1. Crazy, eccentric, or mentally unstable (informal).
    • You'd have to have a screw loose to jump off that cliff into the water.
    • Some people think he has a screw loose because of his strange ideas.
    • She's a bit screw-loose, but she's also the most creative person I know.
Antonyms
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