Eurypterida

plural noun

Eu·​rypter·​i·​da
ˌyu̇rə̇(p)ˈterədə,
-u̇rə̇(-
: an order of extinct, usually large, aquatic arthropods that lived during the Paleozoic era, had a cephalothorax with six pairs of limbs of which the last pair were usually shaped like paddles and a tapering abdomen of 13 segments, and included the largest known arthropods, some exceeding 6 feet (1.8 meters) in length

Word History

Etymology

New Latin, from Eurypterus, included genus (from eury- + -pterus) + -ida

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Cite this Entry

“Eurypterida.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Eurypterida. Accessed 2 Dec. 2022.

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