What is the name of the catastrophic destruction of Númenor in J.R.R. Tolkien’s legendarium?

The catastrophic destruction of Númenor is called the Downfall of Númenor in J.R.R. Tolkien’s legendarium.

Númenor was an island kingdom created for Men who had aided the Elves during the First Age. Over time, many Númenóreans became jealous of the Elves’ immortality and fearful of death. Sauron exploited those fears after allowing himself to be taken to Númenor.

Under Sauron’s influence, King Ar-Pharazôn attacked Aman, the land of the Valar. Ilúvatar then changed the shape of the world: Númenor was overwhelmed, and Aman was removed from the ordinary world.

The event is also known as the Akallabêth, a Quenya name meaning “The Downfallen.” It should not be confused with the War of Wrath, which ended the First Age and occurred long before Númenor’s destruction.