Maniac

1. (n.) A person raving with intense enthusiasm; an insane person.

2. (n.) A raving lunatic; a madman.

Thesaurus Entries

aliene, batty, bedlamite, berserk, borderline case, crackbrain, cracked, crackpot, crazed, crazy, delirious, dement, demented, demoniac, deranged, energumen, enthusiast, fan, fanatic, fiend, flake, fou, frantic, freak, frenetic, frenzied, furious, idiot, kook, loon, loony, lunatic, mad, madman, meshuggenah, non compos, noncompos, nut, phrenetic, psychopath, psychotic, rabid, raging, ranting, raving lunatic, screwball, unsound, violent, weirdo, wild, zealot