Breadcrumb Home > Thesaurus > C Synonyms of cysteine Find synonyms for: Noun 1. cysteine, amino acid, aminoalkanoic acid usage: an amino acid containing sulfur that is found in most proteins; oxidizes on exposure to air to form cystine WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of cysteine (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Jewish Holidays, 2010-2030 (A.M. 5770-5791) Western Christian Holidays, 2010-2030 12 Steps to a New Year New Year's Resolution to Slim Down? Martin Luther King Speeches Books of the Bible: Old Testament Books in Order ✖ Related Content Daily Word Quiz: internecine Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language