# on vs ou

> English confusable word pair

## The two words

### on
*adjective · IPA /ɒn/ · frequency rank #13*
In the state of being active, functioning or operating.

### ou
*noun · IPA /ˈəʊ.uː/ · frequency rank #10,099*
A probably extinct species of Hawaiian honeycreeper, Psittirostra psittacea.

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