Fr.: aplatissement dynamique
A measure of the extent to which mass has been shifted from the polar regions of a (spinning) body toward its equator (Ellis et al., 2007, Planetary Ring Systems, Springer).
From L. ob- "toward" + latus, abstracted from its opposite, prolatus "lengthened."
Pax "oblate," of unknown etymology.
Fr.: sphéroïde aplati
An ellipsoid produced by rotating an ellipse through 360° about its minor axis. Compare with → prolate spheroid.
The property possessed by a round body that is flattened at the poles.
Noun from → oblate.
Fr.: aplatissement optique
(polar flattening) The ratio of the difference between equatorial and polar diameters to the equatorial diameter. A sphere has an oblateness of 0; an infinitely thin disk has an oblateness of 1 (Ellis et al., 2007, Planetary Ring Systems, Springer).