1610s, "one who lengthens (an action)," from Medieval Latin protractor, agent noun from Latin protrahere "to draw forward" (see protraction); sense of "instrument for drawing angles" first recorded 1650s.
双语例句
1. Use your protractor to construct an equilateral triangle.
用量角器作一个等边三角形.
来自《简明英汉词典》
2. This compass serves as a protractor.
这个罗盘可用作分度规.
来自辞典例句
3. To draw to scale by means of a scale and protractor; plot.
测绘用圆规和量角器划线和角; 标绘.
来自互联网
4. Screen angle indicator: A protractor with many co - centre circles.