[countable] a small piece of wire that is used in a device (called a stapler) and is pushed through pieces of paper and bent over at the ends in order to fasten the pieces of paper together订书钉  ➡  picture at office (Economics 经济学) something that is produced by a country and is important for its economy（一国的）主要产品，支柱品◆Copper is a staple of the local economy.铜是当地经济的支柱产品。a large or important part of sth主要部分◆Business clients are the staple of luxury hotels (= their main customers).商业客户是豪华型宾馆的主要顾客。