Definitionen
1.NounA 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 x/a + y/b + z/c = 1.
2.NounSuch a surface used as a model of the shape of the earth."Here the geoid is thirty meters below the ellipsoid."
3.AdjectiveShaped like an ellipse; elliptical.
4.AdjectiveOf or pertaining to an ellipse; elliptic.
5.AdjectiveHaving the tridimensional shape of an ellipse rotated on its long axis.