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wacko

[ wak-oh ]
/ ˈwæk oʊ /
Slang.
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noun, plural wack·os.
Also wack. an eccentric, strange, or odd person.
adjective
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Also whack·o [hwak-oh, wak-oh] /ˈʰwæk oʊ, ˈwæk oʊ/ .

Origin of wacko

First recorded in 1970–75, Americanism;see wacky, -o

Words nearby wacko

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use wacko in a sentence

British Dictionary definitions for wacko

wacko
/ (ˈwækəʊ) informal /

adjective
mad or eccentric
noun plural wackos
a mad or eccentric person

Word Origin for wacko

C20: back formation from wacky
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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