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 The similarity between Jimmy Carr and Milhouse petting the horseshoe crab is uncanny. Bethy Squires, Vulture, 1 Jan. 2022 The best comparison is the 2003 SARS outbreak, which was caused by a close cousin of the virus that causes COVID-19 and eventually traced back to a single population of horseshoe crab bats. Erin Schumaker, ABC News, 8 Apr. 2021 Researchers pointed to the 2003 SARS outbreak, which was caused by a close cousin of the virus that causes COVID-19 and eventually traced back to a single population of horseshoe crab bats. Erin Schumaker, ABC News, 30 Mar. 2021 The race to a vaccine: The horseshoe crab's fluorescent blue blood is its best line of defense against toxins. Ashley Shaffer, USA TODAY, 22 Sep. 2020 The story of the horseshoe crab is a lesson in humility. Tim Prudente, baltimoresun.com, 31 Dec. 2020 Humans owe a debt to the strange-looking, ancient horseshoe crab. Alex Fox, Smithsonian Magazine, 8 June 2020 Back in the late 1990s and early 2000s, there was concern over the fate of the horseshoe crab. Doug Fraser, USA TODAY, 16 June 2020 Starting at $25, adopters receive a digital photo of a horseshoe crab and adoption certificate, plus a copy of its annual newsletter. Jennifer Nalewicki, Smithsonian Magazine, 5 May 2020

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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Time Traveler for horseshoe crab

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The first known use of horseshoe crab was in 1797

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Dictionary Entries Near horseshoe crab

horseshoe clam

horseshoe crab

Horseshoe Curve

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Statistics for horseshoe crab

Last Updated

11 Jan 2022

Cite this Entry

“Horseshoe crab.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/horseshoe%20crab. Accessed 24 Jan. 2022.

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More from Merriam-Webster on horseshoe crab

Britannica.com: Encyclopedia article about horseshoe crab

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