Wikipedia
Mesklin
Mesklin is a fictional supergiant planet created by Hal Clement and used in a number of his hard science fiction stories.
It is distinctive for the interaction of its strong gravity with the centrifugal force due to its fast rotation, originating, according to Clement's original calculations, a gee force gradient, starting at 3 g on the equator, and ending at 665 g on the planet's poles.