plural noun
Ex·​o·​cy·​cloi·​da | \ ˌek(ˌ)sōˌsīˈklȯidə \

Definition of Exocycloida

: an order of sea urchins comprising forms with the periproct posterior or oral in position and including the heart urchins and sand dollars

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History and Etymology for Exocycloida

New Latin, from exo- + cycl- + -oida

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Cite this Entry

“Exocycloida.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Exocycloida. Accessed 27 Feb. 2021.

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