# CMS vs cos

> English confusable word pair

## The two words

### CMS
*name · frequency rank #18,042*
Initialism of Chicago Manual of Style.

### cos
*noun · IPA /kɑs/ · frequency rank #6,553*
Synonym of romaine lettuce, a long-leaved variety of lettuce.

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