[hahy-pur-buh-loid] 
a quadric surface having a finite center and some of its plane sections hyperbolas. Equation: x 2/a2 + y2/b2 − z2/c2 = 1. |
hy·per·bo·loid (hī-pûr'bə-loid')  (click for larger image in new window) n. Either of two quadric surfaces generated by rotating a hyperbola about either of its main axes and having a finite center with certain plane sections that are hyperbolas and others that are ellipses or circles. hy·per'bo·loid'al (-loid'l) adj. |
| hyperboloid (hī-pûr'bə-loid') Pronunciation Key
Either of two surfaces generated by rotating a hyperbola about either of its main axes and having a finite center, with certain plane sections that are hyperbolas and others that are ellipses or circles. |
hyperboloid
the open surface generated by revolving a hyperbola (q.v.) about either of its axes. If the tranverse axis of the surface lies along the x axis and its centre lies at the origin and if a, b, and c are the principal semi-axes, then the general equation of the surface is expressed as x2/a2 y2/b2 - z2/c2 = 1.
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