wacko

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

Definition of wacko

 (Entry 1 of 2)

: wacky

wacko

noun
variants: or less commonly whacko

Definition of wacko (Entry 2 of 2)

: a person who is wacky also : psycho

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Synonyms & Antonyms for wacko

Synonyms: Adjective

balmy, barmy [chiefly British], bats, batty, bedlam, bonkers, brainsick, bughouse [slang], certifiable, crackbrained, cracked, crackers, crackpot, cranky [dialect], crazed, crazy, cuckoo, daffy, daft, demented, deranged, fruity [slang], gaga, haywire, insane, kooky (also kookie), loco [slang], loony (also looney), loony tunes (or looney tunes), lunatic, mad, maniacal (also maniac), mental, meshuga (or meshugge), moonstruck, non compos mentis, nuts, nutty, psycho, psychotic, scatty [chiefly British], screwy, unbalanced, unhinged, unsound, wacky (also whacky), wud [chiefly Scottish]

Synonyms: Noun

bug, crackbrain, crazy, fool, fruitcake, head case, loon, loony, lunatic, maniac, nut, nutcase, nutter [British slang], psycho, psychopath, sickie, sicko

Antonyms: Adjective

balanced, compos mentis, sane, sound, uncrazy

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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

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, "Skelton: Why Americans still don’t have meaningful gun controls," 11 Aug. 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, "Skelton: Why Americans still don’t have meaningful gun controls," 11 Aug. 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. Los Angeles Times, "Gun control has been doomed by single-issue voters. Will that ever change?," 8 Aug. 2019 But the downside of the mockery is glibness; if only the racists and terrorists of the world came as clearly labeled as this flagrantly wacko crew. Joe Morgenstern, WSJ, "‘BlacKkKlansman’ Review: Running on Fury," 9 Aug. 2018 Ashley also seems to think that whoever killed the girls did it for popularity, a wacko theory that gets put to the test when she and John are collectively shunned at the house party. Emma Dibdin, Harper's BAZAAR, "Sharp Objects Episode 6: Camille Is in Deep Trouble," 13 Aug. 2018 Just a few years ago, McCain called Paul and fellow Sen. Ted Cruz, R-Texas, ‘‘wacko birds’’ for their filibuster blocking then-CIA nominee John Brennan. Lisa Mascaro, BostonGlobe.com, "McCain is still up for a fight, even as he battles a deadly illness," 12 May 2018 Berry reminded Cruz supporters that Arizona Sen. John McCain had called Cruz a wacko bird and Cruz had voted in opposition of Senate Majority Leader Mitch McConnell more than 80 times. Jeremy Wallace, Houston Chronicle, "Beto O'Rourke says Pelosi, Schumer don't understand Texas," 6 Apr. 2018 Bolton is a more serious and well-disciplined version of the chaotic Steve Bannon, or the president’s first national security advisor, the wacko Mike Flynn. Trudy Rubin, Philly.com, "What H.R. McMaster's exit and John Bolton's arrival mean for the next three dangerous months | Trudy Rubin," 23 Mar. 2018

Recent Examples on the Web: Noun

Now, all those wackos who’ve been writing to me with their problems can write to her. Rick Kogan, chicagotribune.com, "On the 100th birthday of Ann Landers, a play, a typewriter and a lot of memories," 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, "Heisler: Lakers pray for shot at Lonzo Ball (and the father that comes with him)," 12 May 2017

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.

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First Known Use of wacko

Adjective

1965, in the meaning defined above

Noun

1936, in the meaning defined above

History and Etymology for wacko

Adjective

by alteration

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Statistics for wacko

Last Updated

11 Sep 2019

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Time Traveler for wacko

The first known use of wacko was in 1936

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More Definitions for wacko

wacko

noun

English Language Learners Definition of wacko

US, informal : a person who is crazy or very strange and unusual

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