plural noun

: the oldest surviving order of sea urchins containing the most primitive of living forms, all lacking peristomial gills and sphaeridia but having an apically located anus see cidaridae

Word History


New Latin, from Cidaris + -oida

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Dictionary Entries Near Cidaroida

Cite this Entry

“Cidaroida.” Dictionary, Merriam-Webster, Accessed 22 Sep. 2023.

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