# hyperboloid

[hahy-pur-buh-loid]

- a quadric surface having a finite center and some of its plane sections hyperbolas. Equation: x 2/a 2 + y 2/b 2 − z 2/c 2 = 1.

## Origin of hyperboloid^{}

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

## Examples from the Web for hyperboloid

### Historical Examples

#### At the top it is gathered into a dome in the form of a hyperboloid, pierced near the vertex with an aperture 12 feet in diameter.

Old and New LondonWalter Thornbury

#### In the first case the surface is called an Hyperboloid of one sheet, in the second an Hyperbolic Paraboloid.

# hyperboloid

- 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 x ²/ a ² + y ²/ b ² – z ²/ c ² = 1 (one sheet) or x ²/ a ² – y ²/ b ² – z ²/ c ² = 1 (two sheets) where a, b, and c are constants

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

# hyperboloid

[hī-pûr′bə-loid′]

- 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.

The American Heritage® Science Dictionary
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