# peroneus tertius

> English word · Noun · IPA /pɛ.ɹə(ʊ)ˌniː.əs ˈtɜː.ti.əs/

## Definitions
1. A small muscle of the leg, sometimes absent, that arises from the lower portion of the fibula, inserts on to the dorsal surface of the base of the fifth metatarsal bone, and acts to dorsiflex and evert the foot.

## Etymology
Borrowed from New Latin peroneus tertius, clipping of mūsculus peroneus tertius (“third peroneal muscle”).

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