/ɑːk; ɑrk/ n 1 part of the circumference of a circle or some other curved line 弧（圆周或其它曲线的一部分）. =>illus at circle 见circle之插图. 2 thing with this shape 弧形物: the arc of a rainbow 虹的弧形. 3 luminous electric current passing across a gap between two terminals 电弧; 弧光.v (pt, pp arced / B:kt; Brkt/, pres p arcing/ 5B:kIN; `BrkIN/) [I] form an electric arc 形成电弧; 产生弧光.