cylindroids

Noun

cylindroid (plural cylindroids)

1. A cylinder with elliptical cross-section.
   • The intrados of a simple vault is generally formed of the portion of the surface of a cylinder, cylindroid, or sphere, never greater than that of half the solid; and the springing lines of the coussinet, which terminate the walls from which the vault rises, are generally straight lines, parallel to...1830, Sir David Brewster, The Edinburgh Encyclopaedia, page 523
2. A certain three-dimensional surface described by a moving straight line, used to illustrate the motions of a rigid body and the forces that act upon it.
3. A ribbon-like mucous cast frequently found in the urine in cases of mild irritation of the kidney.