What does AU stand for in fan fiction?

Alternate universe

Fanfic writers use AU as shorthand for "alternate universe." This acronym denotes that a story takes place in a variant of an established fictional universe. In the AU, events may have happened differently, or the universe's rules may not function in quite the same way.

For example, a Harry Potter AU story may imagine a world in which Harry was raised by Voldemort and is thus the story's villain. Or, a Star Wars AU story might imagine a world in which Qui-Gon Jinn survived the events of The Phantom Menace and was able to take Anakin Skywalker on as his Padawan.

The MCU has popularized the AU concept, most notably in the What If? series of animated shorts. As a result, most audiences now understand how AU stories work ... even if they don't know what the AU acronym stands for.


My favorite DC AU is the one where Superman gets adopted by the Waynes and becomes Batman
Woah, that sounds rad
Most fanfic readers and writers enjoy AU fics
Most fanfic readers and writers enjoy AU fics

Related Slang


Updated December 2, 2022

AU definition by

This page explains what the acronym "AU" means. The definition, example, and related terms listed above have been written and compiled by the team.

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