#system_of_weights  a system of units used to express the weight of something
  supertype:  system_of_measurement  a system of related measures
  subtype:  avoirdupois_weight__avoirdupoisweight__avoirdupois__avoirdupoi  a system of weights based on the 16-ounce pound (or 7,000 grains)
  subtype:  troy_weight__troy  a system of weights used for precious metals and gemstones; based on a 12-ounce pound and an ounce of 480 grains

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