Definition of alternating current in English:

alternating current

(also AC)


  • An electric current that reverses its direction many times a second at regular intervals, typically used in power supplies.

    Compare with direct current
    • ‘Some lesions can be shaved down to the level of the surrounding skin, either using a surgical blade or electro-surgery, which uses an alternating current to destroy skin tissue.’
    • ‘In any case Edison's technique was limited by his insistence on using direct current, rather than the standard alternating current that soon took its place when the advantages were recognized.’
    • ‘The company built a new mill and contracted with the Telluride Power and Transmission Company at Ames to supply electricity as an alternating current to both the mine and mill.’
    • ‘In fact, while the national grid relies on alternating current for transmitting electrons, the internal Texas grid transmits via direct current.’
    • ‘LED lights require a transformer to turn alternating current to direct current.’


alternating current