プログレッシブ和英中辞典(第３版)の解説
えんしゅう【円周】
circumference; the circumference of a circle
- 円周500メートルある
It is five hundred meters in circumference.
円周角｜the angle at the circumference
円周率｜pi [pái] ((記号π)); the ratio of the circumference of a circle to its diameter