\ ˈwa-(ˌ)kō How to pronounce wacko (audio) \
variants: or less commonly whacko

Definition of wacko

 (Entry 1 of 2)

: wacky


variants: or less commonly whacko

Definition of wacko (Entry 2 of 2)

: a person who is wacky also : psycho

Synonyms & Antonyms for wacko

Synonyms: Adjective

Synonyms: Noun

Antonyms: Adjective

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Examples of wacko in a Sentence

Noun She's nice but her sister's a real wacko. some wacko has been sending the actress increasingly disturbing letters
Recent Examples on the Web: Adjective Now, however, its inventors are back, and not with just another wacko, attention-getting stunt. New York Times, 10 Mar. 2022 That’s because parents and coaches in the wacko worlds of youth hockey, basketball, soccer and football can be world-class jerks. Washington Post, 6 Dec. 2021 Was Tuesday wacko day for testimony in the Statehouse? Laura Johnston, cleveland, 25 Aug. 2021 This writing team, their imaginations are just wacko brilliant. Gary Goldstein, Los Angeles Times, 2 June 2021 No long lines or voter suppression, beyond some wacko robocalls. Dave Hyde, sun-sentinel.com, 3 Nov. 2020 This was at a time when conservatives were almost ridiculed on law school campuses, where the notion of using the original intentions of the framers to make decisions was seen as laughable, almost wacko, method of constitutional interpretation. Hope Reese, Longreads, 18 Dec. 2019 So after every shooting massacre, when more innocent people are murdered by some wacko with a firearm designed for mass killing, there’s tough talk, screaming and flailing for a few days. George Skelton, The Mercury News, 11 Aug. 2019 Even without that trend, isn’t this line a little wacko? Teddy Greenstein, chicagotribune.com, 18 Oct. 2019 Recent Examples on the Web: Noun Jakubowicz could also be following the example of Jojo Rabbit, a prime illustration of #resistance era wacko-politics, cheap sentiment, and historical revision. Armond White, National Review, 27 Mar. 2020 Now, all those wackos who’ve been writing to me with their problems can write to her. Rick Kogan, chicagotribune.com, 28 June 2018 At the very least, in a game that has known a lot of eccentrics LaVar has put himself in the running for the greatest wacko. Mark Heisler, Orange County Register, 12 May 2017 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'wacko.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of wacko


1965, in the meaning defined above


1936, in the meaning defined above

History and Etymology for wacko


by alteration

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Dictionary Entries Near wacko

Wackenroder solution



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Cite this Entry

“Wacko.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/wacko. Accessed 19 Aug. 2022.

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