Bible Dictionaries
Echinoidea

Webster's Dictionary

(n. pl.) The class Echinodermata which includes the sea urchins. They have a calcareous, usually more or less spheroidal or disk-shaped, composed of many united plates, and covered with movable spines. See Spatangoid, Clypeastroid.

Bibliography Information
Webster, Noah. Entry for 'Echinoidea'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​e/echinoidea.html. 1828.