nuclear winter

WordReference Random House Learner's Dictionary of American English © 2026

ˈnu•cle•ar ˈwin•ter, n. [countable]

1. Meteorology worldwide darkness and cold that some believe could result from extensive dust clouds produced by nuclear war.

WordReference Random House Unabridged Dictionary of American English © 2026

nu′clear win′ter, 

1. Military, Physics, Meteorology the general devastation of life, along with worldwide darkness and extreme cold, that some scientists believe would result from a global dust cloud screening out sunlight following large-scale nuclear detonations.

• 1980–85

Collins Concise English Dictionary © HarperCollins Publishers::

nuclear winter noun

1. a period of extremely low temperatures and little light that, it has been suggested, would occur as a result of a nuclear war