# millimeter vs millimetre

> English confusable word pair

## The two words

### millimeter
*noun · IPA /ˈmɪləˌmitɚ/ · frequency rank #24,517*
US spelling of millimetre.

### millimetre
*noun · frequency rank #47,195*
An SI/MKS unit of measure, the length of ¹⁄₁₀₀₀ of a metre. Symbol: mm

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