echinoid

[ih-kahy-noid, ek-uh-noid]

adjective

belonging or pertaining to the class Echinoidea, comprising mainly sea urchins and sand dollars.

noun

any echinoderm of the Echinoidea.

Origin of echinoid

1850–55; < New Latin Echinoidea; see echinus, -oidea

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for echinoid

Historical Examples of echinoid

A pair of ciliated epaulettes on each side of and behind the ciliated ring is very characteristic of some Echinoid larv.
The Works of Francis Maitland Balfour, Volume II (of 4)
Francis Maitland Balfour
The rows of plates in an Echinoid which are not perforated for the emission of the "tube-feet."
The Ancient Life History of the Earth
Henry Alleyne Nicholson

British Dictionary definitions for echinoid

echinoid

noun

any of the echinoderms constituting the class Echinoidea, typically having a rigid ovoid body. The class includes the sea urchins and sand dollars

adjective

of or belonging to this class

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012