os·​tra·​cod | \ ˈä-strə-ˌkäd How to pronounce ostracod (audio) \
variants: or less commonly ostracode \ ˈä-​strə-​ˌkōd How to pronounce ostracod (audio) \

Definition of ostracod

: any of a subclass (Ostracoda) of very small aquatic crustaceans that have the body enclosed in a bivalve carapace, the body segmentation obscured, the abdomen rudimentary, and only seven pairs of appendages

Examples of ostracod in a Sentence

Recent Examples on the Web Bioluminescent ostracod crustaceans, like tiny fireflies of the sea, have a gland that makes their bioluminescent goo. Quanta Magazine, 16 Aug. 2021 Although giant in name and more than 30 times the size of the average ostracod, this species is still only around an inch long. Thomas Page, CNN, 2 July 2021 Researchers had previously described ostracod sperm from fossils found in Romania, but those dated back to less than 15,000 years ago. Daniel Cressey, Scientific American, 14 May 2014 Scientists announced the discovery of giant sperm inside a female ostracod trapped in Burmese amber. Rafil Kroll-zaidi, Harper's Magazine, 24 Nov. 2020 The sperm belong to an ancient ostracod, a tiny crustacean with a two-piece shell similar to a clam and shrimp-like legs that poke out of the shell’s opening. Theresa Machemer, Smithsonian Magazine, 21 Sep. 2020 The previously unknown species of crustacean, now named Myanmarcypris hui, resembles a modern day mussel and is an example of an ostracod. Amy Woodyatt, CNN, 17 Sep. 2020 Oakley and Ellis studied ten groups of organisms, including fireflies, octopuses, sharks and tiny crustaceans called ostracods. Quanta Magazine, 1 Dec. 2016 Modern ostracods today are similarly well-endowed and some produce absolutely humongous sperm, ten times the size of the male himself. Tim Laman, National Geographic, 14 Feb. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ostracod.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ostracod

1865, in the meaning defined above

History and Etymology for ostracod

from the base of New Latin Ostracoda, neuter plural, borrowed from Greek ostrakṓdēs "like an earthern pot (of a crab shell), testaceous," from óstrakon "earthen vessel, potsherd" + -ōdēs "having the qualities of" (originally, "smelling of," s-stem adjective from the base of ózein "to smell, give off an odor," as in anthemṓdēs "smelling like flowers" > "flowery, blooming") — more at ostracon, odor

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The first known use of ostracod was in 1865

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Cite this Entry

“Ostracod.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ostracod. Accessed 27 Jan. 2022.

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Britannica.com: Encyclopedia article about ostracod


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