plural noun Blas·toi·dea \blaˈstȯidēə\

Definition of Blastoidea

  1. :  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

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Origin and Etymology of blastoidea

New Latin, from blast- + -oidea

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capable of being understood in two ways

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