Acidaspis

noun

Ac·​i·​das·​pis

ˌa-sə-ˈda-spəs

: a genus of trilobites mostly with long spines found in the Ordovician, Silurian, and Devonian

Word History

Etymology

New Latin, from Greek akid-, akis + New Latin -aspis

First Known Use

1843, in the meaning defined above

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