what does nuclear winter mean?

NUCLEAR WINTER as NOUN

Meaning
- a long period of darkness and extreme cold that scientists predict would follow a full-scale nuclear war
- a layer of dust and smoke in the atmosphere would cover the earth and block the rays of the sun
- most living organisms would perish
Hypernyms(s) nuclear winter is a kind of… Example: animal is a hypernym of mammal, plant is a hypernym of flower
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