plural noun

: a class, formerly considered a division of Crinoidea, of extinct Paleozoic short-stemmed or stemless pelmatozoan echinoderms shaped somewhat like a flower bud and having five ambulacral areas with slender appendages along their margins and flattened tubes along their internal surface
adjective or noun

Word History


New Latin, from blast- + -oidea

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Dictionary Entries Near Blastoidea

Cite this Entry

“Blastoidea.” Dictionary, Merriam-Webster, Accessed 9 Jun. 2023.

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