oyster mushroom definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
any of various fan-shaped mushrooms having gills, esp. an edible one (Pleurotus ostreatus) with a short, pale-colored stem, that grows on tree trunks
oyster mushroom definition by American Heritage Dictionary
Any of several edible mushrooms of the genus Pleurotus, having a soft, flavorful, grayish cap.