[ yoo-bik-wi-tin ]
/ yuˈbɪk wɪ tɪn /


a small protein, present in all eukaryotic cells, that participates in the destruction of defective proteins and in the synthesis of new proteins.

Origin of ubiquitin

First recorded in 1985–90; ubiquit(ous) + -in1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for ubiquitin

/ (juːˈbɪkwɪtɪn) /


biochem a small polypeptide, found in most eukaryotic cells, that combines with other proteins to make them susceptible to degradation

Derived forms of ubiquitin

ubiquitination, noun

Word Origin for ubiquitin

C20: from ubiquitous + -in
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for ubiquitin

[ yōō-bĭkwĭ-tĭn ]


A polypeptide found in all eukaryotic cells, including plant cells, that participates in a variety of cellular functions including protein degradation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.