horseshoe crab


Definition of horseshoe crab

: any of several closely related marine arthropods (order Xiphosura and class Merostomata) with a broad crescentic cephalothorax, six pairs of legs, and a spikelike tail especially : one (Limulus polyphemus) of coastal waters from Maine to the Yucatán Peninsula

Note: The horseshoe crab is often said to have five pairs of legs since the first pair is greatly reduced in size and used mainly for feeding. All the legs of the horseshoe crab end in claws except for the last pair of legs which have leaflike expansions used mainly for pushing.

… a horseshoe crab … is a Swiss army knife of jointed limbs—for walking, swimming, grasping, shredding, and defending.
— Carl Zimmer … the horseshoe crab has changed little since an ancestor was fossilized 150 million years ago … National Geographic

called also king crab

Examples of horseshoe crab in a Sentence

Recent Examples on the Web

But horseshoe crabs aren't scary, they're just misunderstood. David Grossman, Popular Mechanics, "Study: Horseshoe Crabs Really Are Arachnids, Just Like Spiders," 28 Feb. 2019 The horseshoe crab's new family is just further emphasizes how much left there is to discover about these creatures. David Grossman, Popular Mechanics, "Study: Horseshoe Crabs Really Are Arachnids, Just Like Spiders," 28 Feb. 2019 Anyone taking or possessing horseshoe crabs without a license can be charged with an infraction that can be paid by the U.S. mail. Christopher Keating,, "House Votes on Satellite Dishes, Horseshoe Crabs," 11 Apr. 2018 Tanks are filled with fish and sea creatures; brave kids can gently (with two fingers) touch lobsters, quahogs, horseshoe crabs, sea stars, and other marine life., "How to do Cape Cod on a budget," 6 June 2018 Among the sea life present were lobsters, horseshoe crabs, and shellfish. Michael Walsh, Courant Community, "Mystic Aquarium Touch Tank Visits Avon Library," 3 July 2018 Each spring, shorebirds migrating from South America to the Arctic stop on the sands of Delaware Bay to feast on masses of horseshoe crab eggs. Washington Post, "Bird flu hot spot: Scientists track virus in huge migration," 28 June 2018 With the state facing major issues on the budget deficit, pensions, highway tolls, casino gambling, and gun control, the legislature found time Wednesday to vote on satellite dishes and horseshoe crabs. Christopher Keating,, "House Votes on Satellite Dishes, Horseshoe Crabs," 11 Apr. 2018 The aquarium boasts a touch pool with horseshoe crabs, rays, and baby zebra sharks, as well as special opportunities to feed sting rays, sea turtles, and sharks. Matt Villano, Sunset, "Top 10 Things to Do in Las Vegas with Kids," 22 Jan. 2018

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

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First Known Use of horseshoe crab

1797, in the meaning defined above

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Last Updated

28 Mar 2019

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The first known use of horseshoe crab was in 1797

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