a. and sb. [f. mod.L. spīnigrad-us.] a. adj. Of or belonging to the Spinigrada, a class of echinoderms that move by means of spines or spinous processes. b. sb. An echinoderm of this class.
1841. E. Forbes, Brit. Starfishes, 19. Ophiuridæ, or Spinigrade Echinodermata. Ibid. They are Spinigrade animals,… their progression being effected … by means of five long flexible-jointed processes … furnished with spines.
1864. Intell. Observ., IV. 251. The Star-fishes are divided according to their mode of locomotion into Spinigrades, moving by means of spines—Cirrhigrades, by suckers—and Pinigrades, by fins.
