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soft-shell clam

noun
  1. an edible clam, Mya arenaria, inhabiting waters along both coasts of North America, having an oval, relatively thin, whitish shell.

Origin of soft-shell clam

An Americanism dating back to 1790–1800
Also called long clam, long-neck clam, soft clam, steamer, steamer clam.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for soft-shell clam

soft-shell clam

noun
  1. any of several marine clams of the genus Mya, esp M. arenaria, an edible species of coastal regions of the US and Europe, having a thin brittle shellSometimes shortened to: soft-shell Compare quahog
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012