What does "trochoid" mean?

Trochoid: (Anat.) Admitting of rotation on an axis; -- sometimes applied to a pivot joint like that between the atlas and axis in the vertebral column.

Additional senses

  1. 2.(Zoöl.) Top-shaped; having a flat base and conical spire; -- said of certain shells.
  2. 3.(Zoöl.) Of or pertaining to the genus Trochus or family Trochidæ.

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