A C89509 NCPDP StrengthUnitOfMeasure Terminology C48512 Milliequivalent Milliequivalent A unit of relative amount of a substance equal to one thousandth of an equivalent weight. C C89510 NCPDP QuantityUnitOfMeasure Terminology C48519 Ounce Ounce The traditional unit of mass. The avoirdupois ounce is equal to 1/16 pound, or 28.349 5 grams, or 0.911 457 troy ounce.