meltdown

[ melt-doun ]
/ ˈmɛltˌdaʊn /

noun

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.
a quickly developing breakdown or collapse: a bond-market meltdown; the meltdown of a marriage.
Informal. a sudden loss of control over one’s feelings or behavior: My toddler had a meltdown when I tried to leave the house.

Origin of meltdown

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

Example sentences from the Web for meltdown

British Dictionary definitions for meltdown

meltdown
/ (ˈmɛltˌdaʊn) /

noun

(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
informal a sudden disastrous failure with potential for widespread harm, as a stock-exchange crash
informal the process or state of irreversible breakdown or decline the community is slowly going into meltdown

Scientific definitions for meltdown

meltdown
[ mĕltdoun′ ]

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

Cultural definitions for meltdown

meltdown

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.