nounThe American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
An oyster (Ostrea edulis) having a round flat shell and a metallic taste, native to northern Europe and cultured primarily in the northwestern United States and Maine. Also called flat oyster.