oyster

noun

oys·​ter ˈȯi-stər How to pronounce oyster (audio)
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The oysters tasted like taking a shot of the sea and chasing it with scallion oil. — Anna Grace Lee, Vogue, 2 July 2026 On the way to the oyster farm, Luke asks about a ring Joy is wearing, which turns out to be from an engagement that ended badly. — Rafaela Bassili, Vulture, 30 June 2026 The small village is world-renowned for its excellent oysters, a delicacy that has been harvested here since Roman times. — Tia Lovisa Moreira, Travel + Leisure, 2 July 2026 The life-threatening species that's found in water can also sicken or kill people who eat contaminated seafood, such as raw oysters infected with the bacteria. — Stephanie Armour, CBS News, 1 July 2026 See All Example Sentences for oyster

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

Time Traveler
The first known use of oyster was in the 13th century

Phrases Containing oyster

Rhymes for oyster

See All Rhymes for oyster

Browse Nearby Words

oylet
oyster
oyster agaric
See all Nearby Words

Cite this Entry

“Oyster.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/oyster. Accessed 7 Jul. 2026.

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Kids Definition

oyster

noun
oys·​ter ˈȯi-stər How to pronounce oyster (audio)
: 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

More from Merriam-Webster on oyster

Nglish: Translation of oyster for Spanish Speakers

Britannica.com: Encyclopedia article about oyster

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