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Synonyms

wacky

American  
[wak-ee] / ˈwæk i /
Also whacky

adjective

Slang.
wackier, wackiest
  1. odd or irrational; crazy.

    They had some wacky plan for selling more books.


wacky British  
/ ˈwækɪ /

adjective

  1. slang eccentric, erratic, or unpredictable

"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

Other Word Forms

Etymology

Origin of wacky

First recorded in 1935–40; apparently whack (noun, as in out of whack ) + -y 1

Explanation

Something that's wacky is weird or nutty or silly. Your goofy uncle who wears a funny hat and does magic tricks at the dinner table is wacky. Use the adjective wacky when you're talking about someone with a ridiculous sense of humor. Clowns are, by definition, wacky, for example. Most people have at least one wacky relative, and some are lucky enough to have entire wacky families. Wacky comes from the nineteenth century British slang term whacky, which arose from whack, specifically the idea of getting whacked on the head so hard that it turns you wacky.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Wacky character traits get trotted out merely for visual dazzle, not to generate any intrigue.

From The Wall Street Journal • Mar. 31, 2026

This would lead to the creation of the Wacky Soap Box Racers, in which the makeshift cars would careen through painted facades of cartoon-ish animals cheering on the guests.

From Los Angeles Times • Dec. 22, 2025

Dick Dastardly was a character in 1960s animated TV series Wacky Races - and several other cartoons and films since - who would try to win by utilising underhand tactics.

From BBC • Oct. 30, 2024

TEMPE, Ariz. – Wacky things happen for Washington in the Arizona desert.

From Seattle Times • Oct. 8, 2022

There were also a felt pennant from Disneyland and a rubber-banded stack of cartoony cards for something called Wacky Packages.

From "Escape from Mr. Lemoncello's Library" by Chris Grabenstein

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