sea urchin

noun

: any of numerous echinoderms (class Echinoidea) that are usually enclosed in thin brittle globular tests covered with movable spines

Examples of sea urchin in a Sentence

Recent Examples on the Web The divers harvest abalone, sea urchins and more by venturing into dark waters without the aid of oxygen tanks or professional diving equipment, instead using instruments like nets and hoes. Kimmy Yam, NBC News, 10 Oct. 2024 Scientists have also found toxic concentrations of TNT in Atlantic purple sea urchins, mysid crustaceans and blue mussels. Paul Hockenos, Smithsonian Magazine, 10 Sep. 2024 Long-spined sea urchins (Diadema antillarum) play a vital role in Caribbean coral ecosystems. Lisa S. Gardiner, Smithsonian Magazine, 7 Aug. 2024 Meet the long-spined sea urchin (Diadema antillarum). Krista Stevens, Longreads, 5 Aug. 2024 See all Example Sentences for sea urchin 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'sea urchin.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1591, in the meaning defined above

Time Traveler
The first known use of sea urchin was in 1591

Dictionary Entries Near sea urchin

Cite this Entry

“Sea urchin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sea%20urchin. Accessed 31 Oct. 2024.

Kids Definition

sea urchin

noun
: any of a class of small marine invertebrate animals that are echinoderms, usually live on or burrow in the sea bottom, and are enclosed in roundish shells covered with spines that can move

More from Merriam-Webster on sea urchin

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