/ Thesaurus / P Synonyms of papillary muscle Find synonyms for: Noun1. papillary muscle, cardiac muscle, heart muscleusage: any of several muscles associated with the atrioventricular valves; "the papillary muscles contract during systole to prevent regurgitation of blood into the atria"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: diaphanous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language