avoirdupois comes from Anglo-French aver de peis ('goods of weight'), from Old French avoir ('property, goods', from Latin habere 'to have') + de + peis ('weight', from Latin pensum, from pendere 'to weigh'). Morphologically, the word is transparent as a compound: its parts remain visible in the modern spelling, while the older history of those parts supplies the deeper ancestry. In modern use, the noun sense is "the system of weights based on a sixteen-ounce pound; informally, bodily weight", which keeps the etymology connected to the word's present dictionary value rather than treating it as a merely historical label. Its nearest semantic neighbors include weight, heaviness, heft, but the etymology gives the word its own historical profile within that field. The principal historical forms in the chain include Latin habere, Latin pendere, which anchor the explanation in named linguistic material.