[U] that which makes it possible to measure things through having number, size, weight, etc 量; 大小; 重量: His reputation as a writer depends more on quantity than quality, ie He writes a lot but he doesn't write very well. 他获得作家的名气靠的是作品的数量而不是质量. * Mathematics is the science of pure quantity. 数学是研究纯数量的科学. 
[C, U] number or amount, esp a large one 数目, 数量（尤指巨大的）: What quantity (ie How many) do you require? 你要求多大的数量? * a small quantity of cutlery 少量的刀叉餐具 * It's cheaper to buy goods in quantity/in large quantities. 大批量购货较便宜. 
(idm 习语) an unknown quantity => unknown.# `quantity surveyor person who estimates the quantity of materials needed for constructing buildings, etc and how much they will cost 估算员（估算建筑材料等用量及其成本者）.