| an electric current that reverses direction at regular intervals, having a magnitude that varies continuously in sinusoidal manner. Abbreviation: ac |
| al·ter·nat·ing current (ôl'tər-nā'tĭng, āl'-) n. Abbr. AC An electric current that reverses direction in a circuit at regular intervals. |
An electric current in which the flow reverses periodically. (Compare direct current (DC).)
Note: In the United States, most household current is AC, going through sixty reversal cycles each second. Electric motors in household appliances are designed to work with current at this rate of reversal.