Clypeastroid \Clyp`e*as"troid\, a. [NL. Clypeaster (L. clupeus
shield + aster star) + -oid.] (Zool.)
Like or related to the genus {Clupeaster}; -- applied to a
group of flattened sea urchins, with a rosette of pores on
the upper side.
[1913 Webster]