# ellipsoid

[ ih-lip-soid ]

noun
1. Geometry. a solid figure all plane sections of which are ellipses or circles. Typical equation: (x2/a2) + (y2/b2) + (z2/c2) = 1.

## Origin of ellipsoid

1
From the French word ellipsoïde, dating back to 1715–25. See ellipse, -oid

## Words Nearby ellipsoid

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

## How to use ellipsoid in a sentence

• Its form is that of an ellipsoid, with a major axis 26 millimetres in length, while the minor axis measures 11 millimetres.

More Hunting Wasps | J. Henri Fabre
• ellipsoid, a surface bearing the same sort of relation to a spherical surface as an ellipse bears to a circle.

• We shall so select the law of contraction that the point S may be at the focus of the meridian section of the ellipsoid.

• If therefore a little hump were discovered on the terrestrial ellipsoid, this discovery would be by itself of no great interest.

• The roof was the long half of an ellipsoid, and the opening in it was over one of the foci of the ellipse of the floor.

Lilith | George MacDonald

## British Dictionary definitions for ellipsoid

ellipsoid

/ (ɪˈlɪpsɔɪd) /

noun
• a geometric surface, symmetrical about the three coordinate axes, whose plane sections are ellipses or circles. Standard equation: x ²/ a ² + y ²/ b ² + z ²/ c ² = 1, where ± a, ± b, ± c are the intercepts on the x-, y-, and z- axes

• a solid having this shape: the earth is an ellipsoid

## Derived forms of ellipsoid

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

## Scientific definitions for ellipsoid

ellipsoid

[ ĭ-lĭpsoid′ ]

1. A three-dimensional geometric figure resembling a flattened sphere. Any cross section of an ellipsoid is an ellipse or circle. An ellipsoid is generated by rotating an ellipse around one of its axes.