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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
QUIZ
THINGAMABOB OR THINGUMMY: CAN YOU DISTINGUISH BETWEEN THE US AND UK TERMS IN THIS QUIZ?
Do you know the difference between everyday US and UK terminology? Test yourself with this quiz on words that differ across the Atlantic.
Question 1 of 7
In the UK, COTTON CANDY is more commonly known as…
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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