whacko

[ hwak-oh, wak-oh ]
/ ˈʰwæk oʊ, ˈwæk oʊ /
Slang.

noun, plural whack·os.

adjective

Origin of whacko

First recorded in 1975–80; whack(y) + -o
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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