弧光的英文：
Arc
n. 弧（度）；弧形物；天穹；弧光
v. 形成拱状物；形成电弧；走弧线
- piercing by electric arc
电弧穿孔 - The beach swept around in an arc.
海滩呈弧形伸展开来。 - The secant of the complement of a directed angle or arc.
余割有向角的余角或弧的余割 - An electric arc is struck by contacting the electrodes.
接触电极便击出电弧。 - A rainbow arced gracefully over the town.
彩虹在小城上空画出了一道优美的弧线。