horseshoe crab

noun

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

Watson only does because of his thesis on horseshoe crab neurobiology. — Caren Chesler, Popular Mechanics, "The Blood of the Crab," 23 Aug. 2019 Those estimates show there are about 25 million to 30 million adult horseshoe crabs in the Delaware Bay alone. — Maddy Lauria, baltimoresun.com, "Using synthetic crab blood substitute in biomedical testing could help save horseshoe crabs and shorebirds," 22 June 2019 The morning of the P.S. 122 trip this month, the younger Mr. Mundy, who is a firefighter and volunteers on the boat, stopped at an island to pick up horseshoe crabs for the students to examine. — Katie Honan, WSJ, "Floating Classroom Teaches New York City Students About Sea Life," 20 June 2019 At the same time, the ocean hosts some of the world's oldest creatures: Jellyfish have been around more than half a billion years, horseshoe crabs almost as long. — Paul Chesley, National Geographic, "Our oceans are under attack by climate change, overfishing," 21 Mar. 2019 Since then, New Jersey has banned the harvest of horseshoe crabs altogether. — Maddy Lauria, baltimoresun.com, "Using synthetic crab blood substitute in biomedical testing could help save horseshoe crabs and shorebirds," 22 June 2019 Khadiza, 14 years old, learned about horseshoe crabs. — Katie Honan, WSJ, "Floating Classroom Teaches New York City Students About Sea Life," 20 June 2019 Data from a federal commission that studies horseshoe crabs along the East Coast shows stability in numbers and even an increase in some regions, now that some states have regulated their harvests. — USA TODAY, "Black Union regiment flag, Notorious BIG, Pikachu the mini pony: News from around our 50 states," 12 June 2019 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

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.