from
The Collaborative International Dictionary of English v.0.48
Avoirdupois \Av`oir*du*pois"\ ([a^]v`[~e]r*d[-u]*poiz"), n. & a.
[OE. aver de peis, goods of weight, where peis is fr. OF.
peis weight, F. poids, L. pensum. See {Aver}, n., and
{Poise}, n.]
1. Goods sold by weight. [Obs.]
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2. Avoirdupois weight.
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3. Weight; heaviness; as, a woman of much avoirdupois.
[Colloq.]
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{Avoirdupois weight}, a system of weights by which coarser
commodities are weighed, such as hay, grain, butter,
sugar, tea.
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Note: 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).
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