# FOSS vs foul

> English confusable word pair

## The two words

### FOSS
*noun · IPA /fɒs/ · frequency rank #33,655*
Initialism of Free and Open Source Software.

### foul
*adjective · IPA /faʊl/ · frequency rank #6,574*
Covered with, or containing unclean matter; dirty.

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