Something that is circular is shaped like a circle.
例句
...a circular hole twelve feet wide and two feet deep...12英尺宽、2英尺深的圆坑Place your hands on your shoulders and move your elbows up, back, and down, in a circular motion.双手置于肩上，肘部向上、向后、向下做圆圈运动。
ADJ
(旅程或路线)环行的，巡回的
A circular journey or route is one in which you go to a place and return by a different route.
例句
Both sides of the river can be explored on this circular walk.沿着这条环行线路走一圈，河的两边都可以看到。
ADJ-GRADED
(论证或理论)循环论证的
A circular argument or theory is not valid because it uses a statement to prove something which is then used to prove the statement.
N-COUNT
(同时发送给很多人的)广告印刷品，通告
A circular is an official letter or advertisement that is sent to a large number of people at the same time.
例句
The proposal has been widely publicised in BBC-TV press information circulars sent to 1,800 newspapers.在英国广播公司电视台发送给1,800家报社的新闻通报中，这项提议得到了广泛的宣传。