What is "dynamic balance"

n. (aeronautics) the state of equilibrium in which centrifugal forces due to a rotating mass (e.g., a propeller) do not produce force in the shaft and so vibration is reduced

Dynamic balance is the branch of mechanics that is concerned with the effects of forces on the motion of a body or system of bodies, especially of forces that do not originate within the system itself, which is also called kinetics.