UNHINGED

brainsick, crazy, demented, disturbed, mad, sick, unbalanced, unhinged

(adjective) affected with madness or insanity; “a man who had gone mad”

Source: WordNet® 3.1

Etymology 1

Verb

unhinged

simple past tense and past participle of unhinge

Adjective

unhinged (comparative more unhinged, superlative most unhinged)

(figuratively, usually, humorous) Mentally ill or unstable.

Etymology 2

Adjective

unhinged (comparative more unhinged, superlative most unhinged)

Not furnished with a hinge.

(philately, of a stamp) Not having ever been mounted using a stamp hinge.

Source: Wiktionary

UNHINGE

Un*hinge", v. t. Etym: [1 st pref. un- + hinge.]

1. To take from the hinges; as, to unhinge a door.

2. To displace; to unfix by violence. Blackmore.

3. To render unstable or wavering; to unsettle; as, to unhinge one's mind or opinions; to unhinge the nerves. Why should I then unhinge my brains, ruin my mind South. His sufferings, nay the revolutions of his fate, had not in the least unhinged his mind. Walpole.

Source: Webster’s Unabridged Dictionary 1913 Edition