Overpoise :: Overpoise (n.) Preponderant weight; a counterbalance.
Overpost :: Overpost (v. t.) To post over; to pass over swiftly, as by post..
Overpower :: Overpower (v. t.) To excel or exceed in power; to cause to yield; to vanquish; to subdue; as, the light overpowers the eyes..
Overpowering :: Overpowering (a.) Excelling in power; too powerful; irresistible.