Quadric
Quadric , adjective
(Mathematics) Of or pertaining to the second degree.
Quadric , noun
(a)
(Algebra) A quantic of the second degree. See Quantic.
(b)
(Algebra) A surface whose equation in three variables is of the second degree. Spheres, spheroids, ellipsoids, paraboloids, hyperboloids, also cones and cylinders with circular bases, are quadrics.