n 1: the product of the momentum of a rotating body and its distance from the axis of rotation; "any rotating body has an angular momentum about its center of mass"; "angular momentum makes the world go round"

nounDate: 1870 a vector quantity that is a measure of the rotational momentum of a rotating body or system, that is equal in classical physics to the product of the angular velocity of the body or system and its moment of inertia with respect to the rotation axis, and that is directed along the rotation axis