meltdown

American  

[melt-doun] / ˈmɛltˌdaʊn /

noun

• meltdowns
  plural

1. the melting of a significant portion of a nuclear-reactor core due to inadequate cooling of the fuel elements, a condition that could lead to the escape of radiation.

2. a quickly developing breakdown or collapse.

   a bond-market meltdown;

   the meltdown of a marriage.

3. Informal. a sudden loss of control over one’s feelings or behavior.

   My toddler had a meltdown when I tried to leave the house.

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meltdown British  

/ ˈmɛltˌdaʊn /

noun

1. (in a nuclear reactor) the melting of the fuel rods as a result of a defect in the cooling system, with the possible escape of radiation into the environment

2. informal a sudden disastrous failure with potential for widespread harm, as a stock-exchange crash

3. informal the process or state of irreversible breakdown or decline

   the community is slowly going into meltdown

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meltdown Scientific  

/ mĕlt′doun′ /

1. Severe overheating of a nuclear reactor core, resulting in melting of the core and escape of radiation.

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meltdown Cultural  

1. The most serious accident that can occur at a nuclear reactor. In a meltdown, the radioactive material in the reactor becomes very hot, melting some or all of the fuel in the reactor. A meltdown may or may not be followed by the release of radioactive material to the environment. A partial meltdown, with very little external radiation, occurred at Three Mile Island (see also Three Mile Island) in 1979; a complete meltdown happened at Chernobyl in 1986.

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Other Word Forms

Noun Inflected Forms

• meltdowns
  plural

Etymology

Origin of meltdown

First recorded in 1960–65; noun use of verb phrase melt down

Example Sentences

See Examples For:

meltdown meltdowns

"It is possible to say that more could have been done, but there was a serious risk of financial meltdown," Tombs reasoned.

From BBC ● Aug. 5, 2026

There are still lessons to be learned from last week’s meltdown at hedge fund Situational Awareness.

From The Wall Street Journal ● Aug. 4, 2026

Whatever it decides, with Mr. Petro in a meltdown over Mr. Cepeda’s loss, it falls to lawmakers, the courts and military to uphold the rule of law.

From The Wall Street Journal ● Jul. 19, 2026

And what sort of impression did Monday’s 4-1 blunder-filled meltdown against Belgium make?

From Los Angeles Times ● Jul. 7, 2026

And if I hadn’t had my meltdown, I wouldn’t now have the name of a lawyer known as “the fixer” clutched in my hand.

From "The Sun Is Also a Star" by Nicola Yoon

Brady, who was born in Bathgate, West Lothian, sought a diagnosis about five years ago as she was experiencing meltdowns.

From BBC ● Jul. 7, 2026

It was one of the biggest software meltdowns of all time, and the stock declined by 36% in the next two weeks.

From Barron's ● Jun. 19, 2026

DFKs’ explosions or meltdowns occur during emotional turbulence.

From Slate ● May 10, 2026

In the aftermath of perhaps the ugliest collapse in the history of a franchise famous for its meltdowns, the New York Mets vowed that changes were on the way.

From The Wall Street Journal ● Dec. 12, 2025

It remains unclear how many people will suffer long-term effects from radiation exposure as a result of the Fukushima meltdowns.

From "Meltdown" by Deirdre Langeland

Related Words

• accident
• adversity
• calamity
• casualty
• cataclysm
• crash
• debacle
• devastation
• disaster
• emergency
• failure
• fiasco
• hardship
• misery
• mishap
• tragedy
• trouble
• wreck