Origin: ME aver de poiz < OFr aveir de peis < aveir, goods (< L habere, to have) + de (< L de), of + peis (< L pensum), weight
See avoirdupois in American Heritage Dictionary 4
Origin: Middle English avoir de pois, commodities sold by weight
Origin: , alteration of Old French aveir de peis, goods of weight
Origin: : aveir, avoir, to have (from Latin habēre; see able)
Origin: + de, of (from Latin dē, from; see de-)
Origin: + peis, pois, weight (from Vulgar Latin *pēsum, from Latin pēnsum, past participle of pendere, to hang; see (s)pen- in Indo-European roots).
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