screw loose

screw loose (plural screws loose)

1. (slang) A state of insanity or eccentricity.

   Synonyms: slate loose, tile loose

   I think there's a screw loose in that brain of hers!

2. (slang, archaic) A state of enmity or disagreement.
   • 1830, Anna Maria Morgan, Horatio in Search of a Wife, page 155:

     I understand there's a screw loose between you two , so I've brought Morton that you may shake hands, and be comfortable together.

   • 1845, Times and Seasons, volume 6, page 1050:

     There is evidently a screw loose between us and some or other of the countries from which, according to royal speeches, we are everlastingly receiving assurances of love and amity.

   • 1880, Sir Augustus Phillimore, The Life of Admiral of the Fleet Sir William Parker, page 404:

     There is a screw loose between the Austrians and French about Venice, which the latter wish to remain as a Republic, and they are also rather angry with Prussia, but I hope the French squadron at Trieste will not come to blows.

• have a screw loose

• John Camden Hotten (1873) The Slang Dictionary