Cidaroida

plural noun
Cid·​a·​roi·​da | \ ˌsidəˈrȯidə \

Definition of Cidaroida

: 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

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History and Etymology for Cidaroida

New Latin, from Cidaris + -oida

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Dictionary Entries Near Cidaroida

cidaris

Cidaroida

-cide

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Cite this Entry

“Cidaroida.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Cidaroida. Accessed 27 Jan. 2022.

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