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

Kahn noted, however, that the Culinary Union has a long history in Las Vegas and has worked with casinos during downturns in the economy — notably in 2008 during the financial meltdown that crippled Las Vegas. David Montero,, "Union workers picket in Las Vegas, worried about pay, security and robots taking their jobs," 6 July 2018 Misunderstandings, meltdowns, and malfunctions define Mercury retrograde, so through August 20, be sure to pay extra close attention to your expression. Aliza Kelly Faragher, Allure, "What Your Sign's July 2018 Horoscope Predictions Mean for You," 29 June 2018 The issues that trigger huge meltdowns and massive fights only make sense some of the time., "The Evolution Of LGBTQ+ Representation On This Black Reality Show," 11 June 2018 McCain's book also sheds light on another 2008 decision that in retrospect was ill-advised: his September 2008 return to Washington, D.C., as Congress was grappling with the financial meltdown. Dan Nowicki, azcentral, "5 takeaways from Sen. John McCain's new memoir, 'The Restless Wave'," 16 May 2018 The deep pain of the housing collapse and the financial meltdown, of course, quickly cured us of any such illusions. Susan Tompor, Detroit Free Press, "How can Fed make investors uncertain? U-M professor says it's obvious," 22 June 2018 Phil Mickelson had the weirdest meltdown The golf course drove golfers up the wall (more on that in a minute), including Lefty, who used a rules loophole to hit a moving ball and move on from No. 13 on Saturday. Charles Curtis, For The Win, "Are you not entertained? The U.S. Open was an all-time classic," 18 June 2018 Sometimes not even your son's favorite toy can keep him from going into meltdown mode. Heather Finn, Good Housekeeping, "How to Make Your Baby's First Haircut as Painless as Possible," 8 June 2018 The fission reactor doesn’t present the same risks—like a meltdown and massive radiation—that a traditional reactor might. Kirsten Korosec, Fortune, "How NASA Might Sustain Life on Mars and the Moon Using Mini Nuclear Reactors," 19 Jan. 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

13 Sep 2018

Look-up Popularity

Time Traveler for meltdown

The first known use of meltdown was in 1956

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More Definitions for meltdown



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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Comments on meltdown

What made you want to look up meltdown? Please tell us where you read or heard it (including the quote, if possible).


a magnificent or impressive array

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