1) Class 2) Class ophiuroidea 1) Ophiothrix 2) Ophiura 
• (n. pl.) 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.
The ophiuroidea are a subclass of stelleroidea. They are the brittle stars. They have a flattened body clearly marked into two regions; the disc and the arms. Tube feet extend from the under surface of the arms, but the groove is closed to form a tube. Locomotion is chiefly by muscular movement of the arms assisted by the feet.
[n] - brittle stars and basket stars
class Ophiuroidea noun brittle stars and basket stars