The Equatorial Bulge refers to the slight outward curvature of a planet's shape at its equator. This phenomenon occurs because a planet, like Earth, rotates on its axis, causing the equatorial region to experience a centrifugal force. As a result, the diameter at the equator is larger than the diameter measured from pole to pole. This bulge is significant in understanding the planet's gravitational field and affects satellite orbits. The equatorial bulge also influences ocean currents and climate patterns, making it an important factor in the study of geophysics and climatology.