1)circumference,圆周闭合曲线图形的周边2)circumference,圆周，周边，周线3)Circumference graph,圆周图形4)periphery,圆周周边5)error of closure of horizon,圆周角闭合差6)Approximation of Circle by Polygons,多边形逼近圆周
用法和例句
According to the second method,we can judge that if error of closure of horizon in many detail unclosed traverse exceed 40 second,if error of closure of angles exceed 40n1 second.
