plural noun
Blas·toi·dea | \blaˈstȯidēə\

Definition of Blastoidea 

: 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

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Other Words from Blastoidea

blastoidean \(ˈ)⸗¦⸗dēən \ adjective or noun

History and Etymology for Blastoidea

New Latin, from blast- + -oidea

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a state of commotion or excitement

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