horseshoe crab

noun

|Updated on: 6 Jun 2018

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 — called also king crab

See horseshoe crab defined for kids

Recent Examples of horseshoe crab from the Web

Octopuses, lobsters and horseshoe crabs use hemocyanin, which means blue blood.

— laura yan, Popular Mechanics, "Green-Blooded Lizards Live With a Pigment That Should Kill Them," 20 May 2018
For nearly 300 million years, the sea creatures resembling modern horseshoe crabs scoured the oceans.

— fiza pirani, ajc, "Tennessee girl discovers 475-million-year-old fossil of rare sea creature," 4 May 2018
Much of Slaughter Beach is a sanctuary for the horseshoe crab, and advertises the designation on its website.

— scott berson, miamiherald, "PETA asked mayor to change Slaughter Beach's name. He told them to 'stay in their lane' | Miami Herald," 2 May 2018
The state of Connecticut is trying to tell the towns what to do.’’ The House also voted 144 — 0 to establish a ban on the hand-harvesting of horseshoe crabs in Stratford in an attempt to preserve the crabs.

— christopher keating, courant.com, "House Votes on Satellite Dishes, Horseshoe Crabs," 11 Apr. 2018
For instance, effective synthetic alternatives exist that could displace some of the widespread use of horseshoe crab blood in pharmaceutical testing.

— nishan degnarain, Fortune, "Commentary: These Technologies Could Save the Northern White Rhino From Extinction," 20 Mar. 2018
The stretch between the three hamlets will return to their historic function, unbroken wetlands that provide a home for thousands of birds, horseshoe crabs and other wildlife.

— frank kummer, Philly.com, "Another N.J. hamlet on the Delaware Bayshore is razed, a victim of sea rise," 12 Dec. 2017
Moonlight even sharpens the visual acuity of horseshoe crabs, which come ashore on certain nights to mate.

— ferris jabr, Smithsonian, "How Moonlight Sets Nature’s Rhythms," 21 June 2017
Built into a teak replica of a fishing skiff in the center of the exhibits area, the pool encourages visitors to get their hands wet to engage with Cownose and Atlantic stingrays, along with horseshoe crabs, hermit crabs and sea anemones.

— joe burbank, OrlandoSentinel.com, "Volusia’s Marine Science Center a hidden treasure at Ponce Inlet," 13 Oct. 2017

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.