any of various orders of echinoid echinoderms having a somewhat globular body of fused skeletal plates studded with long, calcareous, movable spines
Origin of sea urchinso named because of its spines
Any of various echinoderms of the class Echinoidea, having a soft body enclosed in a rounded, radially symmetrical, calcareous skeleton covered with long spines.
white sea urchin
(plural sea urchins)
- attributive form of sea urchin
- sea-urchin look