dynamics

n.pl. 1 (usu. Treated as sing.) A mathematical study of motion and the forces causing it. B branch of any science concerned with forces or changes. 2 motive forces in any sphere. 3 mus. Variation in loudness.

n. That branch of mechanics which treats of the motion of bodies (kinematics) and the action of forces in producing or changing their motion (kinetics). Dynamics is held by some recent writers to include statics and not kinematics.