carbon arc

noun
1.
an electric arc between two carbon electrodes, used mainly for lighting, as in an arc light for a motion-picture projector, or for intense heating, as in the cutting and welding of metals.
Origin
1905-10
British Dictionary definitions for carbon arc

carbon arc

noun
1.
  1. an electric arc produced between two carbon electrodes, formerly used as a light source
  2. (as modifier): carbon-arc light
2.
  1. an electric arc produced between a carbon electrode and material to be welded
  2. (as modifier): carbon-arc welding