Definition of echinoderm
: any of a phylum (Echinodermata) of radially symmetrical coelomate marine animals including the starfishes, sea urchins, and related forms
echinodermatousplay \i-ˌkī-nə-ˈdər-mə-təs\ adjective
Origin and Etymology of echinoderm
New Latin Echinodermata, phylum name, from echin- + -dermata (ultimately from Greek derma skin)
First Known Use: 1835
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