circumscribe
/ˈsɜ:kəmskraɪb; ˌsəkəm`skraɪb/ v[Tn]
1 (fml 文) restrict (sth) within limits; confine 将（某事物）限制於一定范围内; 约束
a life circumscribed by poverty 受制於贫穷的一生.
2 draw a line round (a geometrical figure) so that it touches all the outside points 画（几何图形的）外接圆
circumscribe a square 画正方形的外接圆.