a geometric surface consisting of one sheet, or of two sheets separated by a finite distance, whose sections parallel to the three coordinate planes are hyperbolas or ellipses. Equations x2/a2 + y2/b2 – z2/c2 = 1 (one sheet) or x2/a2 – y2/b2 – z2/c2 = 1 (two sheets) where a, b, and c are constants
hyperboloid in American English
(haɪˈpɜrbəˌlɔɪd)
noun Geometry
1.
a solid often formed by rotating a hyperbola around either main axis: its plane sections are hyperbolas, ellipses, or circles