alternating current


Definition of alternating current

: an electric current that reverses its direction at regularly recurring intervals abbreviation AC

Examples of alternating current in a Sentence

Recent Examples on the Web Battery storage units store energy from the sun as alternating current power for later use. Corrinne Hess, Milwaukee Journal Sentinel, 29 Mar. 2022 Bowen and Blankson-Wood get the alternating current of the brothers’ connection just right. New York Times, 25 Jan. 2022 To avoid large losses of power over long distances, the electricity must be converted from alternating current to direct current, and then back again at the other end. New York Times, 4 Jan. 2022 In 1894, New York World reporter Arthur Brisbane described how electrical inventor Nikola Tesla occasionally absorbed 250,000-volt shocks to demonstrate the safety of alternating current. Eric S. Hintz, Smithsonian Magazine, 8 Dec. 2021 Its tech relies on electrochemical impedance spectroscopy, which uses an alternating current scanned over many frequencies to measure the health of the materials inside a battery cell. Aarian Marshall, Wired, 2 Nov. 2021 Tesla was one of the most prolific and imaginative inventors of the 20th century; his resumé includes the alternating current, induction motor, and many other concepts that remained theoretical for decades after his death. Kyle Mizokami, Popular Mechanics, 29 Oct. 2021 In a rooftop system, that electricity goes into what’s called an inverter that turns it into alternating current electricity that can be used in our homes, according to Schalk. Sarah Bowman, The Indianapolis Star, 17 Nov. 2021 If all devices go off, they are interconnected, typically linked with a red or orange wire to carry a direct current signal in addition to regular alternating current wires for power. Washington Post, 27 Sep. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alternating current.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of alternating current

1833, in the meaning defined above

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Time Traveler for alternating current

Time Traveler

The first known use of alternating current was in 1833

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Dictionary Entries Near alternating current


alternating current

alternating-current resistance

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Statistics for alternating current

Cite this Entry

“Alternating current.” Dictionary, Merriam-Webster, Accessed 16 Aug. 2022.

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More Definitions for alternating current

alternating current


Kids Definition of alternating current

: an electric current that reverses its direction of flow regularly many times per second

More from Merriam-Webster on alternating current

Nglish: Translation of alternating current for Spanish Speakers Encyclopedia article about alternating current


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