plural noun
Palae·​os·​tra·​ca | \ ˌpālēˈästrə̇kə, ˌpal- also -ˈȯs-\

Definition of Palaeostraca

in some classifications
: a class of arthropods comprising the horseshoe crabs, the eurypterids, and sometimes the trilobites — compare merostomata

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Other Words from Palaeostraca

palaeostracan \ ¦⸗⸗¦⸗⸗kən \ adjective or noun

History and Etymology for Palaeostraca

New Latin, from pale- + -ostraca

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