the.com/doomsday

means The day of final judgment or ultimate catastrophic end — the deadline for everything, whether biblical reckoning or civilizational collapse.

from From Old English 'dōmesdæg' — 'dōm' meaning judgment (the same root that gives us 'doom') plus 'dæg,' day. It originally meant simply Judgment Day, the Christian reckoning at the end of the world. The word got a strange detour through English history: the Domesday Book, William the Conqueror's exhaustive 1086 survey of England, was so named because its assessments were considered as final and unappealable as the verdict on Judgment Day itself. So for centuries 'doomsday' lived a double life — one foot in apocalypse, one foot in tax records.