ellipsoid

American  

[ih-lip-soid] / ɪˈlɪp sɔɪd /

noun

1. Geometry. a solid figure all plane sections of which are ellipses or circles. Typical equation: (x 2 / a2 ) + (y 2 / b2 ) + (z 2 / c2 ) = 1.

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adjective

1. ellipsoidal.

ellipsoid British  

/ ɪˈlɪpsɔɪd, ɪlɪpˈsɔɪdəl, ˌɛl- /

noun

1. 1. 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

   2. a solid having this shape

      the earth is an ellipsoid

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ellipsoid Scientific  

/ ĭ-lĭp′soid′ /

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.

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Other Word Forms

• ellipsoidal adjective

Etymology

Origin of ellipsoid

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

Example Sentences

At the start of the experiment, the team molded the clay into a "half ellipsoid" or half of an oval shape.

From Scientific American • Nov. 11, 2023

This is because the Earth is not shaped like a perfect sphere but rather closer to an ellipsoid, with its thickness from the equator being roughly 70,000 feet wider than from the poles.

From Salon • Jul. 26, 2023

Dr. Gendron and Dr. Pletcher then identified the key neurons in the ellipsoid body.

From New York Times • Jun. 13, 2023

Inspecting the displacement ellipsoids shows that the ellipsoid of C1D looks normal, while that of N3D is clearly distended.

From Nature • Mar. 28, 2017

The crucial dispute between Cartesians and Newtonians was over the shape of the Earth: Newton predicted an oblate ellipsoid, or flattened, Earth, while the Cartesians had predicted a prolate ellipsoid, or egg-shaped, Earth.

From "The Invention of Science" by David Wootton