主（电）弧
arc───n.弧（度）；弧光（全称electricarc）；弧形物；天穹；vt.形成电弧；走弧线；n.(Arc)人名；(法)阿尔克；adj.圆弧的；反三角函数的
arc flash───电弧闪光
jerboa arc───跳鼠弧
main───adj.主要的，最大的，最重要的；n.(Main)（美）梅因（人名）；n.（输送水、煤气等的）总管道，主管道；(themains)（水、电等的）供应，供应系统；电源插座；海洋，公海；主帆（mailsail的简称）；（掷骰子游戏中）叫数；斗鸡比赛
fordo arc───福尔多弧
refract arc───折射弧
main scene───主要景点；主场景；主体现场
main objectives───主要目标
arc touch───弧光触摸
Main point: When operating, skill action should be spreaded out with arc, tighten up the belly, harbour chest and action should be consistent.───要领：操作时，技术动作呈弧形动作展开，要收腹含胸，动作连贯。
The eclipse drew an arc across the open sea and uninhabited atolls, making its main landfall on remote Easter Island.───日食在开阔的海域和无人居住的环礁划出一条弧线，日落则在偏远的复活节岛。
This scheme not only eliminates the interference between main arc and pilot arc, but also reduces the deterioration of the tungsten electrode and improves the stability of welding process.───该方案不仅克服了传统方案存在的主维弧干涉现象，而且可大大降低钨电极的烧损，提高焊接过程的稳定性。