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

The stories center on women alone and on the verge of meltdown. Sam Sacks, WSJ, "Fiction: Snakes, Landslides & Adventures in Real Estate," 22 June 2018 The short-term federal funds rate remained at zero percent for seven years after the Fed first drove down short-term rates back in December 2008 to revive the economy during the depths of the financial meltdown. Susan Tompor, Detroit Free Press, "How can Fed make investors uncertain? U-M professor says it's obvious," 22 June 2018 It’s unclear what Washington State will do about Leach in the wake of Sunday night’s Twitter meltdown. Dan Wolken, USA TODAY, "Mike Leach's tweet of an anti-Obama hoax showed why many schools won't hire him," 18 June 2018 The real meat of the episode, though, involves Chris, who is always on the brink of a meltdown. Rebecca Farley,, "The Bachelorette Season 14, Episode 6 Recap: Is Now Really The Time For A "Debate"?," 3 July 2018 Find people who can help create environments to reduce the chance of meltdowns. Veronica Mitchell,, "Ask Veronica — Accepting the truth about dementia-fueled outbursts," 2 July 2018 A half-decade ago, with the housing market meltdown still visible in the rear-view mirror, home searchers in the Milwaukee suburbs had their pick of properties. Bob Dohr, Milwaukee Journal Sentinel, "Top rebounders: which suburbs have bounced back biggest from the housing slump?," 20 June 2018 Which is why Allred’s remarks after the Weinstein meltdown hit so hard. Bryan Smith, Los Angeles Magazine, "How Lisa Bloom Bounced Back From Defending Harvey Weinstein," 8 June 2018 During the evacuation, more than 120,000 people were herded onto buses to escape the meltdown of the Unit 4 reactor, leaving most of their valuables and their pets behind. Jason Daley, Smithsonian, "Chernobyl Puppies Going Up for Adoption in the U.S.," 16 May 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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Statistics for meltdown

Last Updated

8 Nov 2018

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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

: a very fast loss of emotional self-control

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