a surface whose plane sections are all ellipses or circles; "the Earth is an ellipsoid"
a surface, all of whose cross sections are elliptic or circular (includes the sphere)
A three-dimensional mathematical model which approximates the shape of the geoid Many different ellipsoids have been developed for continents or individual countries to minimize local deviations from the geoid The standard global ellipsoid is the World Geodetic System of 1984 (WGS 84) Reference: Peter Dana, The Geographer's Craft
A mathematical model of the earth formed by rotating an ellipse around its minor axis For ellipsoids which model the earth, the minor axis is the polar axis, and the major axis is the equatorial axis An ellipsoid is completely defined by specifying the lengths of both axes, or by specifying the length of the major axis and the flattening
A mathematical formulation of the shape of the Earth which is defined by a semimajor axis and its eccentricity There are 11 official ellipsoids in use throughout the world The Clark Ellipsoid of 1866 is used in North America
a surface whose plane sections are all ellipses or circles; "the Earth is an ellipsoid" in the form of an ellipse
Athree-dimensional ellipse which is used to represent the shape of the surface of the earth A more complete explanation is available in the Standards Section