Cassididae

plural noun

Cas·​sid·​i·​dae

kəˈsidəˌdē,

ka-

: a family of usually large marine gastropod mollusks (order Pectinibranchia) having thick heavy shells of which many are used for making cameos see helmet shell

Word History

Etymology

New Latin, from Cassid-, Cassis, type genus + -idae

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