pelecypod vs scallop

pelecypod and scallop both are nouns.

Word	Noun	Adjective	Verb	Adverb
pelecypod	Yes	Yes	No	No
scallop	Yes	No	Yes	No

As nouns, scallop is a hyponym of pelecypod; that is, scallop is a word with a more specific, narrower meaning than pelecypod:

pelecypod: marine or freshwater mollusks having a soft body with platelike gills enclosed within two shells hinged together
scallop: edible marine bivalve having a fluted fan-shaped shell that swim by expelling water from the shell in a series of snapping motions

Other hyponyms of pelecypod include clam, cockle, oyster, ark shell, blood clam, mussel, escallop, scollop, piddock.

pelecypod (noun)	scallop (noun)
marine or freshwater mollusks having a soft body with platelike gills enclosed within two shells hinged together	edible marine bivalve having a fluted fan-shaped shell that swim by expelling water from the shell in a series of snapping motions
	edible muscle of mollusks having fan-shaped shells; served broiled or poached or in salads or cream sauces
	thin slice of meat (especially veal) usually fried or broiled
	one of a series of rounded projections (or the notches between them) formed by curves along an edge (as the edge of a leaf or piece of cloth or the margin of a shell or a shriveled red blood cell observed in a hypertonic solution etc.)

pelecypod (adjective)	scallop (adjective)
bivalve

pelecypod (verb)	scallop (verb)
	shape or cut in scallops
	fish for scallops
	form scallops in
	decorate an edge with scallops
	bake in a sauce, milk, etc., often with breadcrumbs on top