[1] : The Collaborative International Dictionary of English v.0.48

avoirdupois \av`oirdupois"\ a^v`~erd-upoiz", 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.
      1913 webster

   2. avoirdupois weight.
      1913 webster

   3. weight; heaviness; as, a woman of much avoirdupois.
      colloq.
      1913 webster

   avoirdupois weight, a system of weights by which coarser
      commodities are weighed, such as hay, grain, butter,
      sugar, tea.
      1913 webster

   note: the standard avoirdupois pound of the united states is
         equivalent to the weight of 27.7015 cubic inches of
         distilled water at 62deg 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.
         1913 webster
see also:
aver poise avoirdupois weight troy weight 

[2] : WordNet (r) 2.0

avoirdupois weight
     n : a system of weights based on the 16-ounce pound or 7,000
         grains syn: avoirdupois
see also:
avoirdupois 

Avoirdupois >> A Words
Avoirdupois, definition of term: Avoirdupois
avoirdupois_pag1.html

Weight >> W Words
Weight, definition of term: Weight
weight_pag1.html

Middle Weight >> M Words
Middle Weight, definition of term: Middle Weight
middle+weight_pag1.html

Troy Weight >> T Words
Troy Weight, definition of term: Troy Weight
troy+weight_pag1.html

Imperial Weight >> I Words
Imperial Weight, definition of term: Imperial Weight
imperial+weight_pag1.html

Gross Weight >> G Words
Gross Weight, definition of term: Gross Weight
gross+weight_pag1.html

Body Weight >> B Words
Body Weight, definition of term: Body Weight
body+weight_pag1.html

Dead Weight >> D Words
Dead Weight, definition of term: Dead Weight
dead+weight_pag1.html

Atomic Weight >> A Words
Atomic Weight, definition of term: Atomic Weight
atomic+weight_pag1.html