Doomsday

noun

1. (New Testament) day at the end of time following Armageddon when God will decree the fates of all individual humans according to the good and evil of their earthly lives

   noun.time

   Synonyms crack of doom day of judgement day of judgment day of reckoning end of the world eschaton judgement day judgment day last day last judgement last judgment

   Source: WordNet 3.0

2. an unpleasant or disastrous destiny

   noun.event

   Synonyms day of reckoning doom end of the world

   Source: WordNet 3.0

3. A day of sentence or condemnation; day of death.

   noun

   Source: webster1913