trochal

Adjective

tro=chal

CIDE DICTIONARY

trochal, a. [From Gr. a wheel.].

Resembling a wheel. [1913 Webster]

Trochal disk (Zoöl.), the cephalic disk of a rotifer. It is usually surrounded by a fringe of cilia.

trochal, adj. Zool. wheel-shaped.

Idiom

trochal disc Zool. the retractable disc on the head of a rotifer bearing a crown of cilia, used for drawing in food or for propulsion.

Etymology

Gk trokhos wheel

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