avoirdupois weight n.
A system of weights and measures based on a pound containing 16 ounces or 7,000 grains and equal to 453.59 grams.
| avoirdupois weight (āv'ər-də-poiz') A system of weights and measures based on a pound containing 16 ounces or 7,000 grains, and equal to 453.59 grams. Avoirdupois weight is used in the United States to weigh everything except gems, precious metals, and drugs. Compare troy weight. |
traditional system of weight in the British Imperial System and the United States Customary System of weights and measures. The name derives ultimately from French avoir de pois ("goods of weight" or "property"). The avoirdupois pound contains 7,000 grains, or 256 drams of 27.344 grains each, or 16 ounces of 437 12 grains each. It is used for all products not subject to apothecaries' weight (for pharmaceutical items) or troy weight (for precious metals). It is equal to about 1.22 apothecaries' or troy pounds. Since 1959 the avoirdupois pound has been officially defined in most English-speaking countries as 0.45359237 kg.