2. Avoirdupois weight.
The standard avoirdupois pound of the united states is equivalent to the weight of 27.7015 cubic inches of distilled water at 62 deg fahrenheit, the barometer being at 30 inches, and the water weighed in the air with brass weights. In this system of weights 16 drams make 1 ounce, 16 ounces 1 pound, 25 pounds 1 quarter, 4 quarters 1 hundred weight, and 20 hundred weight 1 ton. The above pound contains 7,000 grains, or 453.54 grams, so that 1 pound avoirdupois is equivalent to 1 31-144 pounds troy. (see troy weight) Formerly, a hundred weight was reckoned at 112 pounds, the ton being 2,240 pounds (sometimes called a long ton).
Origin: oe. Aver de peis, goods of weight, where peis is fr. OF. Peis weight, f. Poids, L. Pensum. See Aver, and poise, n. Excess bodily weight; she found fatness disgusting in herself as well as in others.