Medical Dictionary

Echinoidea

noun pl Ech·i·noi·dea \ˌek-ə-ˈni-dē-ə\

Medical Definition of ECHINOIDEA

:  a class of motile bottom-dwelling echinoderms comprising the sea urchins and related forms
ech·i·noid \ˈek-ə-ˌnid\ noun

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