cystid

‖n. pl. [ NL., fr. Gr. &unr_;&unr_;&unr_;&unr_; a bladder, pouch. ] (Zool.) An order of Crinoidea, mostly fossils of the Paleozoic rocks. They were usually roundish or egg-shaped, and often unsymmetrical; some were sessile, others had short stems. [ 1913 Webster ]