Abstract: A dynamic vibration absorber for a rotating machinery element preferably of the bifilar pendulum vibration absorber type wherein the absorber system includes one or more pair(s) of masses having identical paths of movement relative to the axis of the rotating element whose vibrations are being absorbed, the individual absorber masses of a given pair moving out-of-phase with respect to one another relative to the rotating element wherein a disturbance torque with a frequency that is a multiple of the rotation rate of the rotating element is absorbed by a one-half relative frequency motion of the corresponding half-order absorber pair. The half-order absorber pairs are driven primarily by centrifugal forces, move with a frequency one-half that of the disturbance torque and use non-linear Coriolis forces as the source of the counteracting torque.