Of the mind, faculties, etc.: unbalanced, deranged. Now rare.

Of the mind: Unbalanced, disturbed.

spec. Of persons or the mind.

Of a person: confused; mentally disturbed, insane. Of a situation, event, etc.: confounding, irrational; disturbing.

Of a person, his or her behaviour, etc.: lacking composure or self-assurance; unsettled, impetuous.

spec. in Psychiatry, emotionally or mentally unstable or abnormal; also (originally U.S.), designed for or occupied by disturbed patients.

colloquial (originally U.S.). Of a person: in trouble. Also (now chiefly): exhibiting or characterized by emotional or psychological instability…

Originally U.S. Military slang. Cf. snafu, phr. Of a person: confused, disturbed, or damaged mentally or emotionally. Cf. messed-up, adj. 2.

Originally (of a person): unbalanced, mentally disturbed. Now chiefly (of a situation, event, etc.): confounding, irrational; disturbing.

Of a person: insane, confused, mentally disturbed. Of a situation, event, etc.: disturbing, confounding, irrational. Cf. fucked-up, adj. 2.

colloquial (originally U.S.). Exhibiting or characterized by emotional or psychological instability; damaged; disturbed. Chiefly in predicative…