Either of two quadric surfaces created by rotating a hyperbola about either of their primary axes and having a finite center with specific plane areas being hyperbolas and others which are ellipses or groups.
a certain surface in three-dimensional Euclidean area, the graph of a quadratic with three factors squared and their particular coefficients not all of exactly the same sign.
A surface for the second-order, that is cut by certain planes in hyperbolas; additionally, the solid, bounded simply by such a surface.
A quadric area having a center perhaps not at infinity, many of their airplane sections hyperbolas.
A hyperbola of a greater order.
a quadric surface created by turning a hyperbola around its main axis