alternator

American  

[awl-ter-ney-ter, al-] / ˈɔl tərˌneɪ tər, ˈæl- /

noun

Electricity.

1. a generator of alternating current.

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alternator British  

/ ˈɔːltəˌneɪtə /

noun

1. an electrical machine that generates an alternating current

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Etymology

Origin of alternator

First recorded in 1890–95; alternate + -or ²

Explanation

An alternator is a generator that powers a running vehicle's electrical components and maintains the battery's charge. If your car won't start, you might need to replace the battery — or you may have a broken alternator. Alternators are devices that convert mechanical energy, usually rotational force from an engine or turbine, into electrical energy. Alternators get their name from the alternating current (A/C) that they create. They are an essential part of any car, keeping the battery charged and powering the headlights, stereo, and heated seats. Large power generators, yachts, and some trains also rely on alternators to keep their electrical systems running.

Example Sentences

I’ve had to pay $1,000 for a new alternator for my 2007 Lexus.

From MarketWatch • Mar. 17, 2026

How the kit fits inside a van, powered by an optional EcoFlow Smart Generator with portable solar panels, roof-mounted solar panels, and the van’s alternator.

From The Verge • Jun. 27, 2022

He can change a transmission, replace an alternator, diagnose the weird sounds and, in his free time, he is restoring a 1938 Packard Six initially purchased brand new by his great-grandparents.

From Seattle Times • Aug. 4, 2021

A few days later, a customer was yelling at Garcia about an alternator when he got a call from his father’s doctor saying the hospital needed to remove his father from life support.

From Washington Post • Apr. 8, 2021

If it were the alternator, the battery would be dead and the lights wouldn’t come on.

From "The Serpent King" by Jeff Zentner