Ophiurioidea
O`phi`u`ri`oi´de`a
| n. pl. | 1.(Zool.) 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. |