oyster

noun

oys·​ter ˈȯi-stər 

often attributive

1

a

: any of various marine bivalve mollusks (family Ostreidae) that have a rough irregular shell closed by a single adductor muscle and include commercially important shellfish

b

: any of various mollusks resembling or related to the oysters

2

: something that is or can be readily made to serve one's personal ends

the world was her oyster

3

: a small mass of muscle contained in a concavity of the pelvic bone on each side of the back of a fowl

4

: an extremely taciturn person

5

: a grayish-white color

Examples of oyster in a Sentence

Recent Examples on the Web

Guests can fill their plates with everything from crab legs and shrimp to oysters, scallops, and other seafood favorites. — Abby Price, Southern Living, 19 Aug. 2026

Gaddis loves hunting for oyster plates (which can fetch prices in the thousands of dollars) and other unusual pieces that can mingle with contemporary dishes and vases. — Rachel Silva, Martha Stewart, 19 Aug. 2026

Besides the distinctive shape of their shells, which may have a smooth or ridged surface, scallops differ from clams, mussels, and oysters in being the only bivalves that swim freely as adults. — Encyclopedia Britannica, 18 Aug. 2026

Its menu is part-market, part-Premier, where guests can order light fare like salads, meats and cheeses, sandwiches, oysters, peel-and-eat shrimp and a full list of wine by the glass and cocktails. — Katelyn Umholtz, Kansas City Star, 18 Aug. 2026

Word History

Etymology

Middle English oistre, borrowed from Anglo-French oistre, ostre, going back to Latin ostrea, ostreum "bivalve mollusk, oyster," borrowed from Greek óstreion, óstreon, of uncertain origin

Note: Greek óstreion has traditionally been taken to be a derivative, with a suffix -ei-, of a stem going back to Indo-European *h₃esth₁-r-, from the base *h₃esth₁- "bone." See note at ostracon.

First Known Use

13th century, in the meaning defined at sense 1a

Phrases Containing oyster

• European flat oyster
• European oyster
• Olympia oyster
• oyster bed
• oyster crab
• oyster cracker
• oyster drill
• oyster mushroom
• oyster plant
• seed oyster
• the world is someone's oyster
• vegetable oyster

Rhymes for oyster

• cloister
• moister
• royster

Kids Definition

oyster

noun

oys·​ter ˈȯi-stər 

: any of various marine mollusks that include important edible shellfish and have a rough uneven shell made up of two hinged parts and closed by a single muscle