off (one's) nut

off (one's) nut

Crazy or insane. I think you're off your nut for changing careers this late in life, but, hey, follow your dreams. He's off his nut if he thinks he can get that engine fixed by this weekend.
See also: nut, off
Farlex Dictionary of Idioms.

off your nut

out of your mind; crazy. informal
See also: nut, off
Farlex Partner Idioms Dictionary

ˌoff your ˈnut

(British English, informal, spoken) crazy: Is he completely off his nut?
Nut is an informal word for your head.
See also: nut, off
Farlex Partner Idioms Dictionary

off one’s nut

1. mod. crazy; out of one’s head. Don’t pay any attention to her. She’s off her nut.
2. mod. alcohol intoxicated. Those guys are so off their nuts!
See also: nut, off
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • off one’s nut
  • off your nut
  • be off (one's) nut
  • off one's head, rocker, etc.
  • (I've) got to take off
  • be off (one's) chump
  • be off (one's) trolley
  • be off (one's) rocker
  • be off for (something)
  • be off for sth