| any echinoderm of the class Ophiuroidea, having the body composed of a central, rounded disk from which radiate long, slender, fragile arms. |
| brittle star n. Any of various marine organisms of the class Ophiuroidea, related to and resembling the starfish but having long slender arms. Also called ophiuroid. |
brittle star
any of the 2,000 living species of marine invertebrates comprising the class Ophiuroidea (phylum Echinodermata). Their long, thin arms-usually five and often forked and spiny-are distinctly set off from the small disk-shaped body. The arms readily break off but soon regrow-i.e., are regenerated
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