center of gravity
n//ˌsɛn.təɹ əv ˈɡɹæv.ə.ti//tyngdpunkt
(physics) A point, near or within a body, through which its weight can be assumed to act when considering forces on the body and its motion under gravity. This coincides with the center of mass in a uniform gravitational field.
(metaphorical) The most central or important part of something, which its other parts are considered in relation to.