Ophiurioidea

{ ‖O′phi‐u′ri‐oi″de‐a (?), ‖O′phi‐u‐roi″de‐a (?), } n. pl. [NL., fr. Gr. ὄφισ serpent + ουρἄ tail + εἰ̑δοσ form.] (Zoöl.) A class of star-shaped echinoderms having a disklike body, with slender, articulated arms, which are not grooved beneath and are often very fragile; — called also Ophiuroida and Ophiuridea. See Illust. under Brittle star.