el·lip·tic·i·ty /ɪˌlɪpˈtɪsəti, (ˌ)ɛ-/
橢圓率
El·lip·tic·i·ty 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 difference between the equatorial and polar semidiameters, divided by the equatorial; thus, the ellipticity of the earth is ¹/₂₉₉₆₆.
Note: ☞ Some writers use ellipticity as the ratio of the difference of the two semiaxes to the minor axis, instead of the major.
◄ ►
ellipticity
n : the property possessed by a rounded shape that is flattened
at the poles; "the oblateness of the planet" [syn: oblateness]