trochoidal

[Eng. trochoid; -al.] 1. Ord. Lang. & Geom.: Pertaining to a trochoid; partaking of the nature of a trochoid; as the trochoidal curves, such as the epicycloid, the involute of the circle, the spiral of Arch i me des, . 2. Anat .: Of or pertaining to a kind of articula tion, in which one bone is inserted in another like an axle-tree, so that there can be a motion like that of a wheel. The first and second vertebræ of the neck are thus articulated. †troch-o-li-tēş, 8. [Pref. trocho- , and Gr. lithos =a stone.] Palæont .: A synonym of Lituites (q.v.).