In Norse mythology, what is the battle of the end of the world called?

Ragnarok, in Scandinavian mythology, is the end of the world of gods and men. According to those two sources, the Ragnarök will be preceded by cruel winters and moral chaos. Giants and demons approaching from all points of the compass will attack the gods, who will meet them and face death like heroes. The sun will be darkened, the stars will vanish, and the earth will sink into the sea.

Source: Britannica