Word Study
trochal
CIDE DICTIONARY
trochal, a. [From Gr. a wheel.].
Resembling a wheel. [1913 Webster]
OXFORD DICTIONARY
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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