Definition of avoirdupois noun from the Oxford Advanced Learner's Dictionary

 

avoirdupois

 noun
noun
BrE BrE//ˌævədəˈpɔɪz//
 
, BrE//ˌævwɑːdjuːˈpwɑː//
 
; NAmE NAmE//ˌævərdəˈpɔɪz//
 
[uncountable]
 
jump to other results
the system of weights based on the pound Word Origin Middle English (denoting merchandise sold by weight): from Old French aveir de peis ‘goods of weight’, from aveir ‘to have’ (infinitive used as a noun, from Latin habere) + peis ‘weight’ from an alteration of Latin pensum ‘weight’, from the verb pendere ‘weigh’.
See the Oxford Advanced American Dictionary entry: avoirdupois