An Apocalypse is defined by the Cambridge dictionary as
1. a very serious event resulting in great destruction and change
2. the total destruction and end of the world as described in the biblical book of Revelation
The word „apocalypse“ is Greek and stands for „uncovering“. It’s a disclosure of knowledge or revelation. Today the term is more commonly used in connection with a catastrophic event. There have been prophecies of the end of the world since the beginning of humanity. Even some of the oldest conventions contained a fatale scenario.
However, in most of them there is no mention of a total destruction of the world. It is rather described as a beginning of a new age.