How do Christians imagine 2nd coming of Jesus?

[Gwaithmir]

Wrong! To wit: https://en.wikipedia.org/wiki/Book_of_Revelation

Catholics call it The Apocalypse.

From the link you supplied:

The Book of Revelation (often called the Revelation to John, Apocalypse of John, the Revelation from Jesus Christ from its opening words, the Apocalypse, The Revelation, or simply Revelation) is the final book of the New Testament, and consequently is also the final book of the Christian Bible. Its title is derived from the first word of the Koine Greek text: apokalypsis, meaning "unveiling" or "revelation" (before title pages and titles, books were commonly known by their incipit (first words)). The Book of Revelation is the only apocalyptic document in the New Testament canon (although there are short apocalyptic passages in various places in the Gospels and the Epistles, and an extended apocalyptic passage in the Book of Daniel in the Old Testament).[a] Thus, it occupies a central place in Christian eschatology.

Note that nowhere does it say that the book is called "Revelations." 

Your link shows that I'm right.

Both Protestants and Catholics can call the book either "The Revelation of John," or "The Apocalypse of John," since "apocalypse" means "revelation" in Greek.

https://www.nytimes.com/2012/04/08/books...agels.html

Well, excuse me. I didn't realize I was dealing with a grammar nazi.