Ar ‧ ma ‧ ged ‧ don /ˌɑːməˈɡedn $ ˌɑːr-/ BrE AmE noun [singular, uncountable]
[ Date: 1800-1900 ; Language: Greek ; Origin: place of a great battle at the end of the world, described in the Bible ]
a terrible battle that will destroy the world:
a nuclear Armageddon