# alternator

/ˈɔɫtɝˌneɪtɝ/ (US) · /ˈɔltənˌeɪtɐ/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/alternator
Updated: 2026-05-20

## Definition

a machine that changes electricity from a direct current to an alternating current. It is usually found in a car to keep the battery charged while the engine runs.

For teachers: a device that converts direct current (DC) to alternating current (AC). In automotive contexts, it refers to the component that generates electrical power for the vehicle's systems and recharges the battery.

## Examples

- The car's battery died because the alternator was broken.
- The mechanic checked the alternator to see if it was providing enough power to the car's electrical system.
- Modern vehicles rely on a high-efficiency alternator to supply the necessary electrical energy for both the internal combustion engine and the various electronic components of the vehicle.

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