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Comm. law. The name of a peculiar weight. This kind of weight is so named in distinction from the Troy weight. One pound avoir du pois contains 7000 grains Troy; that is, fourteen ounces, eleven pennyweights and sixteen grains Troy a pound avoir du pois contains sixteen ounces; and an ounce sixteen drachms. Thirty-two cubic feet of pure spring-water, at the temperature of fifty-six degrees of Fahrenheit's thermometer, make a ton of 2000 pounds avoir du pois, or two thousand two hundred and forty pounds net weight. Dane's Abr. c. 211, art. 12, 6. The avoir du pois ounce is less than the Troy ounce in the proportion of 72 to 79; though the pound is, greater. Eneye. Amer. art. Avoir du pois., For the derivation of this phrase, see Barr. on the Stat. 206. See the Report of Secretary of State of the United States to the Senate, February 22d, 1821, pp. 44, 72, 76, 79, 81, 87, for a learned exposition of the whole subject.