melt·​down | \ ˈmelt-ˌdau̇n \

Definition of meltdown

 (Entry 1 of 2)

1 : the accidental melting of the core of a nuclear reactor
2 : a rapid or disastrous decline or collapse
3 : a breakdown of self-control (as from fatigue or overstimulation)

melt down


Definition of melt down (Entry 2 of 2)

intransitive verb

: to suffer a meltdown : collapse

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Synonyms for meltdown

Synonyms: Verb

break down, break up, crack, flip (out) [slang], freak (out), wig (out) [slang]

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Examples of meltdown in a Sentence


fears that an accident could cause meltdown a company experiencing financial meltdown After a long day at the beach, our toddler had a major meltdown in the car on the way home.


apparently beset by personal problems, the actor proceeded to melt down before startled theatergoers
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Recent Examples on the Web: Noun

Keep the makeup simple to avoid meltdowns and mess. Taysha Murtaugh, Country Living, "How to Make a Purr-fect Cat Costume for Halloween," 1 Aug. 2018 Three reactors had meltdowns and a fourth had damage to its building. Mari Yamaguchi,, "Japanese utility eyes scrapping 2nd Fukushima nuclear plant," 14 June 2018 But after this childish meltdown, Claire and Jamie explain that Brianna was raped. Mehera Bonner, Harper's BAZAAR, "Outlander's Season 4 Finale Will Leave You an Emotional Mess," 28 Jan. 2019 Game notes: The Tigers will try to rebound after Friday's seventh-inning meltdown, leading to a 5-4 loss. Marlowe Alter, Detroit Free Press, "Detroit Tigers vs. Seattle Mariners: Time, TV, radio, game info," 19 May 2018 So how to reconcile Phil Mickelson’s mini-meltdown Saturday in the third round of the U.S. Open? Gary D'amato, USA TODAY, "Give Phil Mickelson the benefit of the doubt; he's no cheater," 16 June 2018 That delay has resulted in a massive meltdown of claims processing. Sean Gallagher, Ars Technica, "VA’s software so SNAFU’d that vets were made homeless waiting for benefits," 12 Nov. 2018 The Daiichi Nuclear Power Station, where the 2011 meltdown occurred in the wake of a 7.0-magnitude earthquake, is 75 miles east, separated by several mountain ridges that prevented dangerous radiation from reaching this area. Adam H. Graham, Condé Nast Traveler, "Slow Skiing in Japan's Deep North," 11 Oct. 2018 He was bailed out last weekend as the Colorado Rockies meltdown late after getting Gallardo for five runs in five innings. Jeff Wilson, star-telegram, "Rangers Reaction: Choo worthy of first All-Star selection, but making team won't be easy," 23 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'meltdown.' 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 meltdown


1956, in the meaning defined at sense 1


1956, in the meaning defined above

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Last Updated

15 Feb 2019

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Time Traveler for meltdown

The first known use of meltdown was in 1956

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English Language Learners Definition of meltdown

: an accident in which the core of a nuclear reactor melts and releases radiation
: a very fast collapse or failure
chiefly US, somewhat informal : a very fast loss of emotional self-control

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More from Merriam-Webster on meltdown

Rhyming Dictionary: Words that rhyme with meltdown

Nglish: Translation of meltdown for Spanish Speakers

Britannica English: Translation of meltdown for Arabic Speakers Encyclopedia article about meltdown

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