horseshoe crab

American  

noun

1. a large marine arthropod, Limulus polyphemus, of shallow coastal waters of eastern North America and eastern Asia, having both compound and simple eyes, book gills, a stiff tail, and a brown carapace curved like a horseshoe: a living fossil related to the woodlouse.

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horseshoe crab British  

noun

1. Also called: king crab.  any marine chelicerate arthropod of the genus Limulus, of North America and Asia, having a rounded heavily armoured body with a long pointed tail: class Merostomata

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Etymology

Origin of horseshoe crab

First recorded in 1765–75

Example Sentences

In 1859 Charles Darwin coined the term “living fossil” to describe lineages that have looked the same for tens of millions of years, such as the coelacanth, sturgeon, and horseshoe crab.

From Science Magazine • Mar. 8, 2024

The fish follow along, hoping to eat anything the horseshoe crab misses.

From NewsForKids.net • Oct. 12, 2023

The tri-spine horseshoe crab has survived for more than 100 million years but now faces habitat destruction and overfishing for food and for its blood, used in the development of vaccines.

From BBC • Oct. 10, 2023

Niles and volunteers he organizes have been counting the horseshoe crab eggs since the 1980s and tagging birds since the 1990s.

From Seattle Times • Jul. 30, 2023

She read the pages about the sea urchin, the horseshoe crab, and the moon snail.

From "The Line Tender" by Kate Allen