a. and sb. [mod. f. ECHIN-US + -OID.]
A. adj. Bearing a resemblance to, or having the characteristics of, an Echinus or Sea-urchin.
1851. Richardson, Geol., viii. 208. The fossil species of Crinoid, Asteroid, and Echinoid radiata.
B. sb. An individual of the Order Echinoidea (Class Echinodermata), the characteristics of which are a shell composed of calcareous plates, and locomotion by suckers and spines.
1864. Reader, No. 85. 204/2. Starfishes, Echinoids, or Ophiurans.