go off (one's) dot

go off (one's) dot

To become crazy or mentally unsound; to become extremely foolish or foolhardy. I'm going to go off my dot if I have to hear that blasted song once more! I think Jane's grandmother has gone off her dot lately. You must have gone off your dot if you think that's a good idea!
See also: dot, go, off
Farlex Dictionary of Idioms.
See also:
  • go off (one's) rocker
  • lose (one's) mind
  • lose one's mind
  • lose your mind
  • lose one's buttons
  • lose (one's) buttons
  • lose (one's) marbles
  • lose all one’s marbles
  • lose one’s marbles
  • lose one's marbles