Planar Datum - The true geometric counterpart of a planar datum feature.
Planar Feature of Size - A feature of size that contains two features: the two parallel plane surfaces.
Plus-minus Tolerance - The nominal or target value of the dimension is given first, followed by a plus-minus expression of a tolerance.
Primary Datum - The first datum plane that the part contacts in a dimensional measurement.
Profile- The outline of a part feature in a given plane.
Profile Control - A geometric tolerance that specifies a uniform boundary along the true profile that the elements of the surface must lie within.