A hydrodynamically lubricated sealing element for applications where the pressure of a contained fluid can be significantly greater than the pressure of the seal lubricant. The sealing element retains the pressure of the contained fluid and provides hydrodynamic lubricant pumping activity at the dynamic sealing interface to enhance service life. The invention is particularly suitable for oilfield drilling swivel washpipe assemblies, downhole drilling tools, and rotary mining equipment, and for applications such as artificial lift pump stuffing box assemblies and centrifugal pumps where a rotating shaft penetrates a pressurized reservoir that is filled with abrasive-laden liquids, mixtures, or slurries.