seashell

American  

[see-shel] / ˈsiˌʃɛl /

Or sea shell

noun

1. the shell of any marine mollusk.

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seashell British  

/ ˈsiːˌʃɛl /

noun

1. the empty shell of a marine mollusc

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Etymology

Origin of seashell

before 900; Old English sǣscill (not recorded in Middle English ) see sea, shell

Explanation

Many sea creatures live inside hard, protective cases called seashells. If you find a seashell on the beach, think of it as a tiny abandoned home of a sea creature. You can also call a seashell a shell, although "sea" distinguishes ocean shells from those of freshwater mollusks. If you've ever walked on a beach, you've seen seashells, and maybe even collected some to take home (after checking to make sure no tiny creatures were living inside). Clams, snails, and oysters are all examples of animals that live in seashells. One of the most famous mentions of this word appears in the tongue twister: "She sells seashells by the seashore." Try saying that ten times, fast!

Example Sentences

“You’re going after someone for something that’s just silly. If the guy really was dirty, you should have something on him other than this seashell picture.”

From Salon • May 5, 2026

US Secret Service agents interviewed Comey last May about the seashell photo.

From BBC • Apr. 28, 2026

Each nodule starts as a little fragment, perhaps a shark's tooth or a piece of seashell.

From Scientific American • Aug. 15, 2023

Among his stage costumes in those years, for example, were seashell culottes and red high heels.

From Seattle Times • Mar. 31, 2023

Unfortunately, the average hermit crab isn’t particularly athletic, having to haul a clunky seashell around on its back, so the sports competition part of Abbey’s project sort of fizzled.

From "Flush" by Carl Hiaasen