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
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Echinus Geyser is about 66 feet wide, with a spiky rim made of silica, and is surrounded by rocks that resemble sea urchins.
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Munis Raza, Interesting Engineering, 4 Mar. 2026
The acidic geyser is located in the back basin of the park’s Norris Geyser Basin and is named Echinus for the sea urchin-like rocks that surround the 66-foot-wide geyser (echinus is Latin for sea urchin).
—Evie Carrick, Travel + Leisure, 4 Mar. 2026
Echinus Geyser, located in the back basin of the Norris Geyser Basin at Yellowstone, is about 66 feet wide and is surrounded by rocks that resemble sea urchins.
—Kerry Breen, CBS News, 3 Mar. 2026
The geyser was named after mineralogist Albert Charles Peale visited the geyser in 1878 and thought the rocks surrounding it resembled sea urchins, a group of animals that also contain starfish, brittle stars and sand dollars.
—Julia Jacobo, ABC News, 3 Mar. 2026
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Munis Raza, Interesting Engineering, 4 Mar. 2026
The acidic geyser is located in the back basin of the park’s Norris Geyser Basin and is named Echinus for the sea urchin-like rocks that surround the 66-foot-wide geyser (echinus is Latin for sea urchin).
—Evie Carrick, Travel + Leisure, 4 Mar. 2026
Echinus Geyser, located in the back basin of the Norris Geyser Basin at Yellowstone, is about 66 feet wide and is surrounded by rocks that resemble sea urchins.
—Kerry Breen, CBS News, 3 Mar. 2026
The geyser was named after mineralogist Albert Charles Peale visited the geyser in 1878 and thought the rocks surrounding it resembled sea urchins, a group of animals that also contain starfish, brittle stars and sand dollars.
—Julia Jacobo, ABC News, 3 Mar. 2026
See All Example Sentences for sea urchin
Cite this Entry
“Sea urchin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sea%20urchin. Accessed 13 Mar. 2026.
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