# auth vs aux

> English confusable word pair

## The two words

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

### aux
*adjective · IPA /ˈɔks/ · frequency rank #16,176*
Abbreviation of auxiliary.

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