plural noun
Clyp·​e·​as·​tri·​na | \ -əˈstrīnə, -rēnə\

Definition of Clypeastrina

: a suborder of sea urchins (order Exocycloida) comprising a large number of flattened more or less discoidal sea urchins (as the cake urchins and sand dollars) — compare spatangina

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History and Etymology for Clypeastrina

New Latin, from Clypeaster + -ina

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