A madman, lunatic, maniac.

A man who is insane; a lunatic. Also more generally (also hyperbolically): a person who behaves like a lunatic, a wildly foolish person.

A lunatic person; a person of unsound mind; a madman.

A person who is frantic or frenzied; a ‘lunatic’; a delirious patient. Obsolete.

A woman who is insane. More generally (also hyperbolically): a woman who behaves like a lunatic, a wildly foolish woman.

a brown hare in the breeding season, characterized by much leaping, boxing, and chasing in circles, and taken as the type of something mad.

Nouns, as Bedlam beggar (cf. 5), bedlam-house, bedlam-man; adjs., as bedlam-mad, bedlam-ripe, bedlam-witted.

A mad person. In later use: A religious maniac. Obs.

An inmate of Bethlehem Hospital, London, or of a lunatic asylum, or one fit for such a place, a madman; spec. one of the discharged, but often only…

An insane or delirious person; = frantic, n. Now rare. Perhaps Obsolete.

The Hospital of St. Mary of Bethlehem, used as an asylum for the reception and treatment of the mentally ill; originally situated in Bishopsgate, in…

(the name of) a lunatic, a madman, esp. one claiming to have been licensed to beg on release from the Hospital of St Mary of Bethlehem in London (see…

One having a cracked brain or impaired intellect; a crazy fellow.

A hot-headed or uncontrolled person; a scatterbrain.

A familiar shortening of the male forename Thomas. (The name of) a lunatic; (also) a person who feigns insanity in order to obtain money by begging…

†(a) In early use: a madman; a maniac. Obsolete. rare. (b) A person who acts like a maniac; a reckless, wildly impulsive person. Now also in South…

A mad person, a ‘lunatic’.

An insane or wildly foolish person.

A brainsick person. Obsolete.

A foolish or insane person. Also attributive.

= non compos mentis, n. Obsolete.

A mad person; a person who acts insanely or foolishly.

Nouns, as Bedlam beggar (cf. 5), bedlam-house, bedlam-man; adjs., as bedlam-mad, bedlam-ripe, bedlam-witted.

A lunatic; spec. = Bedlam-beggar at bedlam, n. compounds.

A fanatic; in modern English (originally U.S.): a keen and regular spectator of a (professional) sport, originally of baseball; a regular…

An inmate of Bedlam or of a lunatic asylum; a madman or lunatic.

A crack-brain, a crazy fellow.

A lunatic, a madman. (See A. 1) Obsolete.

A person of ‘cracked’ brain or wandering wits; a giddy, thoughtless person.

With plural agreement. With the. Mad people as a class.

A person affected with mania; a person who is, or looks or behaves as if, mad. Now frequently in trivial use.

Insanity; a person of unsound mind. Obsolete.

= shatter-brain, n.

absol. An insane person. Hence (attributive use of the plural), Appropriated to, set apart for, the insane, as insane asylum, insane ward, etc.

A crazy person, a crack-brain. Obsolete. rare.

A person affected with dementia.

A mad or eccentric person.

A crack-brain, a crazy creature, a crank. Also attributive.

A lunatic.

U.S. slang. An irrational, foolish, or insane person.

A mentally ill person who is highly irresponsible and antisocial and also violent or aggressive; (Psychiatry) a person consistently exhibiting…

Chiefly North American, Australian, and New Zealand. A person who is psychologically disturbed or mentally ill, or (later chiefly, in weakened…

= psychopath, n. rare.

North American colloquial (originally slang). A person who is psychologically disturbed or mentally ill, esp. (in early use) as a result of being…

Esp. in Jewish usage: a mad, crazy, or stupid person; = meshuga, n.

A deranged person; a psychopath.

A mad or foolish person, a lunatic.

colloquial (originally U.S.). A mad or crazy person; an eccentric, a crank.

colloquial. A person who is mentally ill; a psychiatric patient.

An inept or simple-minded person; a fool, an idiot. Also (chiefly Prison slang): a person regarded as mad or mentally unstable. Cf. ding-a-ling, n. 2.

(Also used in full form, Lakes of Killarney). Mad, crazy. Occasionally as n., a mad person.

An eccentric or crazy person; a madman, a crackpot.

colloquial (originally U.S.). A mad, crazy, or eccentric person.

colloquial (originally U.S.). depreciative. A mad or crazy person.

a pot for storing barm; also figurative, an eccentric or mad person.

colloquial (originally U.S.). A crazy, mad, or eccentric person; = nutcase, n.

An insane person; a deranged or unstable person. Also in weakened sense: an eccentric person.

A crazy, mad, or mentally disturbed person; an eccentric. Also (occasionally): a violent person.

A mad or crazy person; (also, occasionally) a violent person. Cf. nutcase, n.

Esp. in Jewish usage: a mad, crazy, or stupid person; = meshuggener, n.

A crazy or eccentric person.

A person whose behaviour is violent and unpredictable, or markedly eccentric; (often hyperbolically) such a person characterized as mentally ill…

A crazy, mad, or eccentric person. Cf. nutcase, n.

British colloquial. Originally and chiefly Scottish. A person regarded as crazy or mentally unstable, esp. one whose behaviour is violent or…

A mad or crazy person; (in weakened sense) an eccentric or unconventional person. Frequently as a term of abuse.

= wack, n.1

slang (originally U.S.). Frequently in form nutbar. A crazy, mad, or eccentric person; = nutcase, n. Cf. nutcake, n. 2.

British slang. A crazy, uncontrolled, or eccentric person; a ‘nutcase’.