Orig. the process of measuring by the *ell; this came to refer both to the measuring and inspection of cloth, and also the fee paid for that service. Aulnage accounts were made up for all home-produced cloth from the 13c to the 14c. These were made by the crown for taxation purposes: the wool industry, being so large, was at the centre of the English economy and crucial to royal revenues. These accounts provide a broad, if not precise, picture of the fortunes and fluctuations of the English sheep industry: before the mid-14c healthy and expanding; after the *Black Death in decline and stagnating. The Latin term was alnagium. [< OldFr. alner = to measure by the *ell.]
Dictionary of Medieval Terms and Phrases. Christopher Coredon with Ann Williams.