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
verb
melted down; melting down; melts down
Definition of melt down (Entry 2 of 2)
: to suffer a meltdown : collapse
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Merriam-Webster unabridged
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Time Traveler for meltdown
The first known use of meltdown was in 1956
See more words from the same year