eu·​phau·​si·​id yü-ˈfȯ-zē-əd How to pronounce euphausiid (audio)
: any of an order (Euphausiacea) of small usually luminescent malacostracan crustaceans that resemble shrimp and in some areas form an important element in marine plankton
euphausiid adjective

Example Sentences

Recent Examples on the Web Although their biological samples were low overall, scientists did find creatures, including small crustaceans called copapods, as well as euphausiids, or krill, a shrimp-like crustacean. San Diego Union-Tribune, 5 Aug. 2019

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

Word History


New Latin Euphasia, a genus of krill (from eu- eu- + Greek phaúsis "lighting, illumination" —from phau-, base of pháe "[it] shines" + -sis -sis— + New Latin -ia -ia entry 1) + -id entry 1 — more at photo-

Note: The genus name Euphausia was introduced by the American geologist and zoologist James Dwight Dana (1813-95) in "Synopsis Generum Crustaceorum Ordinis 'Schizopoda'," The American Journal of Science and Art, 2nd series, vol. 9 (May, 1850), pp. 129-33.

First Known Use

1885, in the meaning defined above

Time Traveler
The first known use of euphausiid was in 1885

Dictionary Entries Near euphausiid

Cite this Entry

“Euphausiid.” Dictionary, Merriam-Webster, Accessed 27 Jan. 2023.

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