A sand dollar.Licensed from iStockPhoto
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio.
any of an order (Clypeasteroida) of flat, round, disklike echinoid echinoderms that live on sandy ocean beds
Used by arrangement with John Wiley & Sons, Inc.
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.
- Any of various thin circular echinoderms of the class Echinoidea, especially Echinarachnius parma, of coastal northern Atlantic and Pacific waters, having a covering of short movable spines.
- The disklike internal skeleton of a sand dollar, having five radially symmetric oblong markings and often a pattern of slotlike holes.