Meaning : (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.
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
Meaning : An unpleasant or disastrous destiny.
Example :
Everyone was aware of the approaching doom but was helpless to avoid it.
That's unfortunate but it isn't the end of the world.
Synonyms : day of reckoning, doom, end of the world