oyster

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of several edible bivalve mollusks of the family Ostreidae, having a rough, irregularly shaped shell attached to the substrate in shallow marine waters. Oysters are widely cultivated for food.
• noun Any of various similar or related bivalve mollusks, such as the pearl oyster.
• noun An edible bit of muscle found in the hollow of the pelvic bone of a fowl.
• noun A special delicacy.
• noun Something from which benefits may be extracted.
• noun Slang A close-mouthed person.
• intransitive verb To gather, dredge for, or raise oysters.

from The Century Dictionary.

• To engage in oyster-fishing; take oysters in any way.
• noun An edible bivalve mollusk of the family Ostreidæ, such as Ostrea edulis, the common species of Europe, and O. virginica, that of the Atlantic coast of the United States.
• noun One of many other bivalves of the same order, but of a different family. Thus, the pearl-oyster belongs to the Aviculidæ.
• noun The oyster-shaped bit of dark meat in the front hollow of the side-bone of a turkey or similar bird.
• noun Figuratively, some profit or advantage which one may seize and hold.
• noun Among packers, steamed oysters packed in hermetically sealed cans: a trade-name.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Zoöl.) Any marine bivalve mollusk of the genus Ostrea. They are usually found adhering to rocks or other fixed objects in shallow water along the seacoasts, or in brackish water in the mouth of rivers. The common European oyster (Ostrea edulis), and the American oyster (Ostrea Virginiana), are the most important species.
• noun A name popularly given to the delicate morsel contained in a small cavity of the bone on each side of the lower part of the back of a fowl.
• noun (Zoöl.) any species of the genus Etheria, and allied genera, found in rivers of Africa and South America. They are irregular in form, and attach themselves to rocks like oysters, but they have a pearly interior, and are allied to the fresh-water mussels.
• noun a breeding place for oysters; a place in a tidal river or other water on or near the seashore, where oysters are deposited to grow and fatten for market. See 1st Scalp, n.
• noun (Zoöl.) See oystercatcher in the vocabulary.
• noun (Zoöl.) a small crab (Pinnotheres ostreum) which lives as a commensal in the gill cavity of the oyster.
• noun a rake or small dragnet for bringing up oysters from the bottom of the sea.
• noun (Zoöl.) The toadfish.
• noun (Bot.) A plant found on the seacoast of Northern Europe, America and Asia (Mertensia maritima), the fresh leaves of which have a strong flavor of oysters.
• noun (Zoöl.) Same as oystercatcher.
• noun (Zoöl.) the shell of an oyster.
• noun a women who deals in oysters.
• noun (Zoöl.) See under Pearl.
• noun (Zoöl.) any spiny marine shell of the genus Spondylus.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Any marine bivalve mollusk of the Family Ostreidae, usually found adhering to rocks or other fixed objects in shallow water along the seacoasts, or in brackish water in the mouth of rivers.
• noun A name popularly given to the delicate morsel of dark meat contained in a small cavity of the bone on each side of the lower part of the back of a fowl.
• noun A pale beige color tinted with grey or pink, like that of an oyster.
• noun colloquial, by analogy A person who keeps secrets and private information to him- or herself.
• adjective Of a pale beige colour tinted with grey or pink, like that of an oyster.
• verb intransitive To fish for oysters.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a small muscle on each side of the back of a fowl
• noun edible body of any of numerous oysters
• noun marine mollusks having a rough irregular shell; found on the sea bed mostly in coastal waters
• verb gather oysters, dig oysters