柯林斯词典protractor /prəˈtræktə/ (protractors) 1. N-COUNT A protractor is a flat, semicircular piece of plastic or metal that is used for measuring angles. 量角器; 分度槼 返回 protractor剑桥词典a device used for measuring and drawing angles . It is usually in the form of half a circle made from transparent plastic with degrees printed on it. 量角器；分度槼 返回 protractor