1. Any of various bivalve mollusks, especially certain edible species.Compare quahog, soft-shell Clam. Informal

2. Many species, such as the quahog and soft-shell Clam, are edible and Tridacna gigas is the largest known bivalve, nearly 1.5 metres long 2.

3. No person engaged in recreational fishing for clams by hand or with hand-held tools shall catch and retain, in any day, more than 300 clams in the aggregate from any or all of the following species: (a) bar clam; (b) bay quahaug; (c) razor clam; and (d) soft-shell clam.