noun
meltdown
Refers to a nuclear reactor meltdown or, by extension, a catastrophic failure or collapse in other contexts (e.g., financial, emotional).
福島第一原発でメルトダウンが起きた。
A meltdown occurred at the Fukushima Daiichi nuclear power plant.
株価の暴落は市場のメルトダウンを引き
The stock market crash triggered a market meltdown.