butter clam 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 a genus (Saxidomus) of large, edible clams found along the Pacific coast of North America
butter clam definition by American Heritage Dictionary
A large, delicately flavored clam of the genus Saxidomus, found on the Pacific coast of North America and having a distinctive shell that was formerly used as money by Native Americans. Also called money shell.