[mo.men.tum] n, pl mo.men.ta or momentums [NL, fr. L, movement] (1610) 1: a property of a moving body that the body has by virtue of its mass and motion and that is equal to the product of the body's mass and velocity; broadly: a property of a moving body that determines the length of time required to bring it to rest when under the action of a constant force or moment
2: strength or force gained by motion or through the development of events: impetus "the campaign gained ~"