\Cyl"in*droid\ (s?l"?n-droid), n. [Gr. ky`lindros
cylinder + -oid: cf. F. cylindro["i]de.]
1. A solid body resembling a right cylinder, but having the
   bases or ends elliptical.
2. (Geom.) A certain surface of the third degree, described
   by a moving straight line; -- used to illustrate the
   motions of a rigid body and also the forces acting on the
   body.