insane.

Definition of insane. in English English dictionary: off the rails; potty
The noise that the neighbour's kids were making was driving Fred potty.; off one's nut; Characterized by insanity or the utmost folly; chimerical; unpractical; as, an insane plan, attempt, etc; Used by, or appropriated to, insane persons; as, an insane hospital; Exhibiting unsoundness or disorder of mind; not sane; mad; deranged in mind; delirious; distracted; demented; {s} mentally ill, mad, crazy; senseless, foolish; mentally deranged or acting that way, as in: They must have been insane to try to outrun the train; Causing insanity or madness; Exhibiting unsoundness or disorded of mind; not sane; mad; deranged in mind; delirious; distracted; See Insanity, 2; Of or pertaining to one who is of unsound mind A legal rather than a psychiatric term; disapproval If you describe a decision or action as insane, you think it is very foolish or excessive. I said, `Listen, this is completely insane.' + insanely in·sane·ly I would be insanely jealous if Bill left me for another woman; afflicted with or characteristic of mental derangement; "was declared insane"; "insane laughter; Term used imprecisely in the federal population censuses to indicate a person who had once possessed mental faculties that had become impaired; afflicted with or characteristic of mental derangement; "was declared insane"; "insane laughter"; very foolish; "harebrained ideas"; "took insane risks behind the wheel"; "a completely mad scheme to build a bridge between two mountains"; Someone who is insane has a mind that does not work in a normal way, with the result that their behaviour is very strange. Some people simply can't take it and they just go insane = mad; deranged; loony; nuts