[ahrk] 
noun, verb, arced [ahrkt] or arcked, arc⋅ing [ahr-king] or arck⋅ing.| 1. | Geometry. any unbroken part of the circumference of a circle or other curved line. |
| 2. | Also called electric arc. Electricity. a luminous bridge formed in a gap between two electrodes. Compare spark 1 (def. 2). |
| 3. | Astronomy. the part of a circle representing the apparent course of a heavenly body. |
| 4. | anything bow-shaped. |
| 5. | to form an electric arc. |
| 6. | to move in a curve suggestive of an arc. |
| electric arc n. A luminous discharge of current that is formed when a strong current jumps a gap in a circuit or between two electrodes. |
ARC abbr.
AIDS-related complex
arc (ärk) Pronunciation Key
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| electric arc
An electric current, often strong, brief, and luminous, in which electrons jump across a gap. Electric arcs across specially designed electrodes can produce very high heats and bright light, and are used for such purposes as welding and illumination in spotlights. Unwanted arcs in electrical circuits can cause fires. Lightning is a case of an electric arc between one cloud and the earth or another cloud, as are sparks caused by discharges of static electricity. |
electric arc
continuous, high-density electric current between two separated conductors in a gas or vapour with a relatively low potential difference, or voltage, across the conductors. The high-intensity light and heat of arcs are utilized in welding, in carbon-arc lamps and arc furnaces that operate at ordinary air pressure, and in low-pressure sodium-arc and mercury-arc lamps.
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