ellipsoid

n. figure in the shape of an ellipse, oval-shaped figure

An ellipsoid is a type of quadric surface that is a higher dimensional analogue of an ellipse. The equation of a standard ellipsoid body in an x-y-z Cartesian coordinate system is where a and b are the equatorial radii (along the x and y axes) and c is the polar radius (along the z-axis), all of which are fixed positive real numbers determining the shape of the ellipsoid.
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Noun
1. a surface whose plane sections are all ellipses or circles; "the Earth is an ellipsoid"
(hypernym) plane figure, two-dimensional figure
Adjective
1. in the form of an ellipse
(synonym) ellipsoidal, spheroidal, non-circular
(similar) rounded

n. ellipsoid, figure in the shape of an ellipse, oval-shaped figure

adj. ellipsoidal, shaped like an ellipse, egg-shaped, oval

(n.)
A solid, all plane sections of which are ellipses or circles. See Conoid, n., 2 (a).
  

(a.)
Alt. of Ellipsoidal