D defs.my
Entry 1 sense Webster, 1913

Ellipticity

· El·lip·tic·i·ty · IPA
01 n. Deviation of an ellipse or a spheroid from the form of a circle or a sphere; especially, in reference to the figure of the earth, the diffe…
  1. 1.
    Deviation of an ellipse or a spheroid from the form of a circle or a sphere; especially, in reference to the figure of the earth, the difference between the equatorial and polar semidiameters, divided by the equatorial; thus, the ellipticity of the earth is <frac:1_29966/.