# capacitor

/kəˈpæsətɝ/ (US) · /kəpˈæsɪtɐ/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/capacitor
Updated: 2026-05-08

## Definition

a small part in an electronic device that stores electricity for a short time. You can think of it like a tiny, fast-charging battery that releases energy when needed.

For teachers: a passive two-terminal electronic component that stores electrical energy in an electric field. It consists of two conducting plates separated by an insulating material, or dielectric.

## Examples

- The technician replaced a broken capacitor on the computer's motherboard.
- When the power supply fluctuates, the capacitor releases its stored charge to keep the circuit running smoothly.
- High-capacity capacitors are essential in modern power electronics for filtering noise from signals and stabilizing the voltage delivered to sensitive microprocessors.

## Usage notes

- Commonly used with verbs like 'charge', 'discharge', or 'leak'.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.