sea urchin


Definition of sea urchin 

: 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

One day Oleinik might meet with a kidney doctor about deep learning algorithms to quantify the extent of kidney damage, and another day a biologist about optimizing images of sea urchins. Cindy Atoji Keene,, "Facing a fear leads to love for the language of computing," 6 July 2018 Milton drove along the border for a bit, then dropped his net and started dragging for sea urchins in Passamaquoddy Bay. Porter Fox, WSJ, "A Seafood Hater Chases Fish in Maine," 6 June 2018 One is dressed with butter and soy sauce and tossed with pieces of sea urchin; another is sweet and simple, tangy with ketchup. New York Times, "Things to Do in NYC: Astoria for a Pool Day, and Open-Mic Night Plus Dumplings in Chinatown," 12 July 2018 At the Rubenstein Arts Center on Duke University’s campus, an image from a microscope makes an alien landscape out of the knobby, radial symmetry of a sea urchin skeleton. Marissa Fessenden, Smithsonian, "Scientific Images Make Dazzling Art In a Duke University Exhibit," 12 July 2018 Geoduck, sea urchin and citrus work in unison in a delicate rice tart that comes to the table under a glass dome white from dry ice. Michael Bauer,, "Atelier Crenn: SF’s newest 4-star restaurant," 29 June 2018 Plus, a seafood tower (clams, snow crabs, mussels, whelks, sea urchin), caribou heart with alder and chanterelle mushrooms, tuna with berries, and chanterelle ice cream. Bridget Hallinan, Condé Nast Traveler, "Recap: Anthony Bourdain's 'Parts Unknown' Visits Newfoundland," 14 May 2018 Starfish feed on a variety of invertebrates, including mussels, sea urchins, clams and snails. Peter Fimrite,, "Starfish on California coast, nearly wiped out by mystery illness, make stunning recovery," 22 June 2018 That’s because the kelp canopy on the periphery of their range had been devoured by sea urchins. Peter Fimrite, San Francisco Chronicle, "Monterey Bay Aquarium’s program to save sea otters revives their habitat," 21 Apr. 2018

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

See More

First Known Use of sea urchin

1591, in the meaning defined above

Keep scrolling for more

Learn More about sea urchin

Share sea urchin

Statistics for sea urchin

Last Updated

2 Sep 2018

Look-up Popularity

Time Traveler for sea urchin

The first known use of sea urchin was in 1591

See more words from the same year

Keep scrolling for more

More Definitions for sea urchin

sea urchin


English Language Learners Definition of sea urchin

: a small sea animal that lives on the ocean floor and is covered in sharp spines

sea urchin


Kids Definition of sea urchin

: a small sea animal that is related to the starfish, lives on the sea bottom, and is enclosed in a roundish shell covered with spines that can move

Keep scrolling for more

More from Merriam-Webster on sea urchin

Spanish Central: Translation of sea urchin

Nglish: Translation of sea urchin for Spanish Speakers Encyclopedia article about sea urchin

Comments on sea urchin

What made you want to look up sea urchin? Please tell us where you read or heard it (including the quote, if possible).


lying above or upon

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
Spell It

Can you spell these 10 commonly misspelled words?


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!