Breadcrumb Home > Thesaurus Cite Synonyms of sustainer Find synonyms for: Noun1. upholder, maintainer, sustainer, supporter, protagonist, champion, admirer, booster, friendusage: someone who upholds or maintains; "firm upholders of tradition"; "they are sustainers of the idea of democracy"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.See also: sustainer (Dictionary) Related Content Daily Word Quiz: parallax Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language Synonyms Index