Avoirdupois, << `av` uhr duh POYZ, >> is a system of weights used for common commodities such as coal, grain, and foodstuffs. The system is used primarily in the United States. The word avoirdupois comes from French words meaning goods of weight. The basis of the system is the pound, which equals 0.454 kilogram. An avoirdupois pound contains 16 ounces or 7,000 grains. Each ounce contains 16 drams, so 1 dram equals 27.344 grains. One grain equals 64.799 milligrams. Two other systems of weight, the Troy and apothecaries’ systems, also have grains that equal 64.799 milligrams. The Troy and apothecaries’ pounds, however, equal 5,760 grains.
