Echinoidea
noun plural
Ech·i·noi·dea
ˌek-ə-ˈnȯi-dē-ə 
: a class of motile bottom-dwelling echinoderms comprising the sea urchins and related forms
Cite this Entry
“Echinoidea.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/Echinoidea. Accessed 22 Jul. 2025.
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