THESAURUS
crackpot
alien, aliene, bedlamite, borderline case, case, character, crackbrain, crank, cuckoo, dement, demoniac, ding-a-ling, dingbat, eccentric, energumen, erratic, fanatic, flake, fou, freak, harebrain, hermit, hobo, idiot, kook, lone wolf, loner, loon, loony, lunatic, madman, maniac, maverick, meshuggenah, natural, noncompos, nonconformist, nut, odd fellow, oddball, oddity, original, outsider, pariah, phrenetic, queer duck, queer fish, queer specimen, rara avis, raving lunatic, recluse, screwball, solitary, strange duck, tramp, type, weirdo, zealot