The definition of an oyster is a bivalve mollusk with an irregular long shell that is normally attached to rocks and that is consumed as food.(noun)
A bivalve mollusk that is taken from the ocean and served raw as part of a seafood buffet is an example of an oyster.
See oyster in Webster's New World College Dictionary
Origin: OFr oistre < L ostrea < Gr ostreon, oyster; akin to osteon, a bone: see ossify
See oyster in American Heritage Dictionary 4
Origin: Middle English oistre
Origin: , from Old French
Origin: , from Latin ostreum, ostrea
Origin: , from Greek ostreon; see ost- in Indo-European roots.
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