Dooms′day′ (do͞omz′dā′), n. [AS. d?mes dāg. See Doom, and Day.] 1. A day of sentence or condemnation; day of death. "My body's doomsday." Shak.
2. The day of the final judgment.
I could not tell till doomsday. Chaucer.
Doomsday Book. See Domesday Book.