flash.o.ver
n.（名词）An unintended electric arc, as between two pieces of apparatus.飞弧：如在两块器械之间产生的一道随意性的电弧The temperature point at which the heat in an area or a region is high enough to ignite all flammable material simultaneously.燃点：能够同时点燃某一区域或范围内所有可燃物所需的温度
