/ Thesaurus / O Synonyms of oyster mushroom Find synonyms for: Noun1. oyster mushroom, oyster fungus, oyster agaric, Pleurotus ostreatus, agaricusage: edible agaric with a soft greyish cap growing in shelving masses on dead woodWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: devout Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language