1911 Encyclopædia Britannica/Allowance
ALLOWANCE (from “allow,” derived through O, Fr. alouer from the two Lat. origins adlaudare, to praise, and allocare, to assign a place; so that the English word combined the general idea of “assigning with approval”), the action of allowing, or the thing allowed; particularly, a certain limited apportionment of money or food and diet (see Dietary).
In commercial usage “allowance” signifies the deduction made from the gross weight of goods to make up for the weight of the box or package, waste, breakages, &c. Allowance, which is customary in most industries, varies according to the trade, district or country; e.g. in the coal trade it is customary for the merchant to receive from the pit 21 cwts. of coal for every ton purchased by him, the difference of 1 cwt. being the allowance for the purpose of making good the waste caused through transhipment, screening and cartage (see Tare and Tret.)