Noun
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
Source: WordNetOn the 8th Day – Nuclear winter documentary (1984) Media * The Cold and the Dark: The World after Nuclear War : A book co-authored by Carl Sagan in 1984 which followed his co-authoring of the TTAPS study in 1983. Source: Internet