A freshwater mussel, usually edible, of the order Unionida in subclass Palaeoheterodonta.
A saltwater mussel, usually edible, of the order Mytilida in subclass Pteriomorphia.
Any of certain other bivalves of somewhat similar appearance, such as the zebra mussel and quagga mussel of the family Dreissenidae in subclass Heterodonta.
A similar edible clam found along coasts around the North Atlantic, generally in deeper waters, the ocean quahog, black quahog, mahogany clam or Icelandic cyprine, Arctica islandica
The largest size of such an edible clam, generally considered only fit for use in chowders and other clam dishes.
An edible clam with a hard shell found along the Atlantic Coast of North America, from species Mercenaria mercenaria, formerly Venus mercenaria.
To dig for quahogs.