1. (n.) An insane person\.

2. (a.) of or pertaining to, or suitable for, an insane person; evincing lunacy; as, lunatic gibberish; a lunatic asylum.

3. (n.) A person affected by lunacy; an insane person, esp. one who has lucid intervals; a madman; a person of unsound mind.

abnormal absurd aliene ass balmy batty bedlamite bereft of reason borderline case born fool brainsick buffoon clown crackbrain crackbrained cracked crackpot crank crazed crazy cuckoo daft deluded dement demented demoniac deprived of reason deranged ding-a-ling disoriented distraught doodle egregious ass energumen fanatic fantastic figure of fun flake flighty fool fou hallucinated harebrain idiot ignoramus insane irrational jackass kook loco loon loony mad maddened madman maniac manic mazed mental mentally deficient meshuggah meshuggenah milksop moon-struck mooncalf neuropath neurotic non compos non compos mentis noncompos not all there not right nut odd of unsound mind off paranoid perfect fool phrenetic potty preposterous psycho psychoneurotic queer raver raving lunatic reasonless schmuck screwball senseless sick softhead sop stark-mad stark-staring mad strange stupid ass tetched tomfool touched unbalanced unhinged unsane unsettled unsound wacky wandering weirdo witless zany