# ubiquitin

> English word · Noun · IPA /juːˈbɪkwɪtɪn/ · frequency rank #67,914

## Definitions
1. Any of a class of small protein, or polypeptide, present in the cells of all eukaryotes, that play a part in modifying and degrading proteins.

## Etymology
From ubiquitous + -in.

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