In the USA, the word "clam" can be used in several different ways: one,'s as a general term covering all bivalve mollusks. The word can also be used in a more limited sense, to mean bivalves which burrow in sediment, as opposed to ones which attach themselves to the substrate (for example oysters and mussels), or ones which can swim and are migratory, like scallops. In addition the word "clam" can be used in an even more limited sense, to mean one or more species of commonly consumed marine biv… (More on Clam)