geoid
Pronunciation:
/ˈdʒiːɔɪd//ˈdʒiˌɔɪd/noun
Definitions
(geodesy) The shape that the surface of the oceans of the Earth would take under the influence of the Earth's gravity and rotation alone, extending also through the continents, disregarding other factors such as winds and tides; that is, a surface of constant gravitational potential at zero elevation.