See eccentric in Webster's New World Roget's A-Z Thesaurus II
adjective
Deviating from the customary:
bizarre, cranky, curious, erratic, freakish, idiosyncratic, odd, outlandish, peculiar, quaint, queer, quirky, singular, strange, unnatural, unusual, weird. (Slang) kooky, screwball. (British Slang) rum, rummy2. See usual
noun
A person regarded as strange, eccentric, or crazy:
crackpot, crazy, lunatic. (Informal) crank, loon, loony. (Slang) cuckoo, ding-a-ling, dingbat, kook, nut, screwball, weirdie, weirdo. See wise
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