PoundForce is a unit of force.
Pound
(Units Package Symbol) Pound is a unit of weight.
PoundsPerSquareInch is a unit of pressure.
Puncheon is a unit of volume.
Radian is a dimensionless measure of plane angle.
Rod
(Units Package Symbol) Rod is a unit of length.
Roentgen is a unit of exposure to X or gamma radiation.
Rontgen is a unit of exposure to X or gamma radiation.
Rydberg is a unit of energy.
Section is a unit of area.