Doomsday is defined as the time of God's final judgment, the day the world ends, or is a time when something terrible or dangerous will happen.
(noun)See doomsday in Webster's New World College Dictionary
noun
Origin: ME domesdai < OE domes dæg < domes, gen. of dom, doom + day
See doomsday in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English domesday
Origin: , from Old English dōmes dǽg
Origin: : dōmes
Origin: , genitive of dōm, judgment; see doom
Origin: + dǽg, day; see Day
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