quadric

[ kwod-rik ]

/ ˈkwɒd rɪk /

Mathematics

of the second degree (said especially of functions with more than two variables).

a quadric function.

a surface such as an ellipsoid or paraboloid as defined by a second-degree equation in three real variables.

Origin of quadric

First recorded in 1855–60; quadr- + -ic

Every conic which has five points in common with a quadric surface lies on the surface.

Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 |Various
Instead of a circle or sphere we may take any conic or quadric.

Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 |Various
Every plane which cuts a quadric surface in a line-pair is a tangent plane.

Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 |Various
The surface itself is therefore called a quadric surface, or a surface of the second order.

Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 |Various

If through one point on a quadric surface no line on the surface can be drawn, then the surface contains no lines.

Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 |Various

quadric

/ (ˈkwɒdrɪk) maths /

having or characterized by an equation of the second degree, usually in two or three variables

of the second degree

a quadric curve, surface, or function