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Synonyms

wacko

American  
[wak-oh] / ˈwæk oʊ /
Also whacko

noun

  • wackos
    plural
  1. Also an eccentric, strange, or odd person.


adjective

  1. wacky.

wacko British  
/ ˈwækəʊ /

adjective

  1. mad or eccentric

"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

noun

  1. a mad or eccentric person

"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

Noun Inflected Forms

Etymology

Origin of wacko

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

Explanation

Describing someone as a wacko is a derogatory way to say they're quirky or eccentric. It may be tempting to call the neighbor who walks his pet peacock on a leash a wacko, but it wouldn't be very nice. You'll often hear someone use the word wacko as a way of dismissing people whose opinions or lifestyle they don't understand or agree with. If your cranky uncle complains about the wackos in town, then he's probably talking about a group of people he doesn't like very well. This informal noun first appeared around 1938, from 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:

Do you look back at the risks you took, with unusual buildings designed by foreign architects with no experience in China, as wacko now?

From The Wall Street Journal ● Apr. 10, 2026

In April, he was expelled from the House of Commons for calling the prime minister a "wacko".

From BBC ● Jan. 8, 2025

"We obviously can't be surprised if we lose. We're not that wacko," he told the outlet.

From Salon ● Nov. 18, 2022

He also tried to warn other law enforcement agencies, he testified, writing to the Capitol Police that Mr. Rhodes was “a friggin’ wacko that the Oath Keepers would be better without.”

From New York Times ● Oct. 6, 2022

For some wacko reason, Ms. Jenna had started to let our after-school class come to the storage room after they had finished their homework.

From "The Stars Beneath Our Feet" by David Barclay Moore

When wackos say this, I pay no attention.

From BBC ● Aug. 13, 2026

These wackos want to ruin everything about your life, but they don’t mind littering.

From Washington Times ● Nov. 20, 2023

"When we began working on this 12 years ago and talked about plastic fragments in water, people took us for wackos and now it is a recognised problem."

From Reuters ● Aug. 25, 2023

By and large, the world is increasingly run by ignoramuses, wackos and psychotics.

From Salon ● Jul. 23, 2019

Maybe she puts this crumb under there before every new patient to sort out the true wackos.

From "Popcorn" by Rob Harrell

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