centigrade
/ˈsentɪgreɪd; `sɛntəˌɡred/ (also Celsius) adj (abbr 缩写 C) of or using a temperature scale with the freezing-point of water at 0 and the boiling-point at 100 摄氏温度计的
a centigrade thermometer 摄氏温度计
20C means twenty degrees centigrade 20C的意思是二十摄氏度. Cf 参看 Fahrenheit. =>App 4, 5 见附录4、 5.