alternating current

noun

: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This allows the battery to manage energy more efficiently and enables alternating current output without separate hardware. Sujita Sinha, Interesting Engineering, 22 Sep. 2025 Electricity comes in two basic flavors, direct current where the electrons simply flow through the conductors and alternating current where the polarity is constantly changing. Sam Abuelsamid, Forbes.com, 19 Sep. 2025 The chair used 1,300 volts of alternating current, developed by Nikola Tesla; Thomas Edison promoted the execution to associate AC with death and thus boost his own direct current system. Lorenzino Estrada, AZCentral.com, 7 Aug. 2025 This involved delivering a pulse of alternating current with a small amplitude, and at a frequency of 2 Hz that has previously been shown to be effective in encouraging axon growth in lab settings. Abhimanyu Ghoshal, New Atlas, 6 July 2025 See All Example Sentences for alternating current

Word History

First Known Use

1833, in the meaning defined above

Time Traveler
The first known use of alternating current was in 1833

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Cite this Entry

“Alternating current.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alternating%20current. Accessed 30 Sep. 2025.

Kids Definition

alternating current

noun
: an electric current that reverses its direction at regular intervals
abbreviation AC

More from Merriam-Webster on alternating current

Last Updated: - Updated example sentences
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