plural noun
Ci·​dar·​i·​dae | \ sə̇ˈdarəˌdē\

Definition of Cidaridae

: a family of sea urchins including all recent members of the order Cidaroida and comprising a number of forms that are widely distributed in warm seas

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History and Etymology for Cidaridae

New Latin, from Cidaris, type genus + -idae

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readily or continually undergoing change

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