plural noun

: 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

Word History


New Latin, from Clypeaster + -ina

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Dictionary Entries Near Clypeastrina

Cite this Entry

“Clypeastrina.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2023.

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