Definition of "ellipsoid" in English

noun

1. (mathematics, geometry) A surface, all of whose cross sections are elliptic or circular (including the sphere), that generalises the ellipse and in Cartesian coordinates (x, y, z) is a quadric with equation x²/a² + y²/b² + z²/c² = 1.

2. (geography) Such a surface used as a model of the shape of the earth.

   • Here the geoid is thirty meters below the ellipsoid.

adjective

1. Shaped like an ellipse; elliptical.

2. (mathematics) Of or pertaining to an ellipse; elliptic.

3. (botany) Having the tridimensional shape of an ellipse rotated on its long axis.