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Synonyms

wacky

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

adjective

Slang.
  • wackier,
    comparative
  • wackiest
    superlative
  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

Derived Forms

Inflected Forms

Adjectives


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.

See Examples For:

Steffi Cao argues that we should be wary of the algorithm that incentivizes mindless scrolling, but there is nonetheless something charming about the wacky human storytelling that drives these videos.

From Slate ● Sep. 28, 2026

The mere fact that there are six increasingly wacky installments should be enough to warrant curiosity.

From Salon ● Sep. 23, 2026

Why it’s worth seeing: The wacky inventiveness Wilson brought to his genius HBO show, “How to With John Wilson,” permeates the film.

From The Wall Street Journal ● Sep. 7, 2026

Obviously, clambering up and down the dangerously steep pass, ferrying goods on horseback or by mule or — for a few wacky, experimental months in the mid-1850s, Army camels — wasn’t workable.

From Los Angeles Times ● Aug. 1, 2026

I could maybe find some mad scientist to cryogenically freeze me, but chances are I’d die in the middle of that wacky experiment.

From "They Both Die at the End" by Adam Silvera

At their peak, bubbles feature IPOs of outfits with much wackier marketing pitches than a name change to something like “AI-squared.”

From The Wall Street Journal ● May 19, 2026

Welcome to the wackier side of geoengineering - deliberately intervening in the Earth's climate system to try to counteract the damage we have done to it.

From BBC ● Mar. 15, 2024

Cahn: The wackier it is, the more people are like, “Oh, it’s a real relationship.”

From Los Angeles Times ● Jun. 13, 2023

This improbable story — a team that trailed in the final minutes of an elimination game of the play-in tournament somehow getting to the NBA Finals — now has an even wackier plot twist.

From Washington Times ● Jun. 5, 2023

It celebrated the wackier moments of the usually strait-laced Trebek, showing him verbally sparring with contestants and arm-wrestling with one.

From Seattle Times ● Jan. 8, 2021

As Regency-era gestures of love go, inaccurate bird impersonations are simultaneously the nerdiest and wackiest.

From Salon ● Jun. 25, 2026

Some of the wackiest ideas will never see the light of day, but the best might end up in one of our tech gift guides.

From The Wall Street Journal ● Jan. 11, 2026

Here's a look back on some of the wackiest costumes that have been donned by runners over the years.

From BBC ● Apr. 22, 2023

Programmers know a majority of TV viewers will only watch video clips of the most poignant or wackiest moment of the Emmys telecast.

From Los Angeles Times ● Sep. 13, 2022

Season after season, gasoline-guzzling couriers crisscross Paris to personally deliver elaborate, often handmade, show invites, as top houses vie for the wackiest or most imaginative idea.

From Seattle Times ● Jul. 7, 2022

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