What does "quadric" mean?

Quadric: Of or pertaining to the second degree.

Additional senses

  1. 2.(a) (Alg.) A quantic of the second degree. See Quantic. (b) (Geom.) 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.

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