plural noun

: a class of Paleozoic short-stemmed or stemless pelmatozoan echinoderms formerly considered an order of Crinoidea having the body commonly somewhat globular or egg-shaped and enclosed in calcareous plates that are usually pierced by a system of pores possibly respiratory in function

Word History


New Latin, from cyst- + -oidea

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Dictionary Entries Near Cystoidea

Cite this Entry

“Cystoidea.” Dictionary, Merriam-Webster, Accessed 20 Feb. 2024.

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