recorded earlier in the mental sense of "to disorder" the mind, etc. (1612) than in the literal one of "to take (a door, etc.) off its hinges" (1616); from un- (2) "opposite of" + hinge (n.). Hinge as a verb meaning "to attach by a hinge" is recorded only from 1758. Related: Unhinged; unhinging.[unhinge etymology, unhinge origin, 英语词源]