noun
end of a century; fin-de-siècle
Often refers specifically to the end of the 19th century and its associated cultural mood of decadence and anxiety. Can be used for any century's end.
19世紀末のパリは芸術の中心地だった。
Paris at the end of the 19th century was a center of art.
世紀末的な退廃の
It's a novel with a fin-de-siècle atmosphere of decadence.
noun
end of the world; apocalypse
Used especially in fiction, games, and speculative contexts to describe a world-ending scenario or apocalyptic setting.
そのゲームは世紀末の荒廃した世界を舞台にしている。
That game is set in a devastated, apocalyptic world.
世紀末的な終末思想が流行した時期もあった。
There was a time when apocalyptic end-of-the-world ideas were popular.