# AU vs auth

> English confusable word pair

## The two words

### AU
*noun · frequency rank #6,867*
Initialism of alopecia universalis.

### auth
*noun · frequency rank #30,696*
Abbreviation of authentication.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/vs/au-vs-auth