# watt

/ˈwɑt/ (US) · /wˈɒt/ (UK)

Source: https://englishreference.com/word/watt
Updated: 2026-08-15

## Senses

### 1. unit of power

noun · CEFR B2 · Technical

a unit that measures how much power an electrical device uses.

For teachers: the International System of Units (SI) unit of power, defined as one joule per second.

- This new LED bulb only uses nine watts but is very bright.
- The engineer calculated that the motor would require several thousand watts of peak power to lift the heavy load at the required speed.

Usage: Usually abbreviated as 'W' in technical contexts; often used with SI prefixes like kilo- or mega-.

## Examples

- This lamp uses a sixty-watt bulb.
- The new solar panels can generate several thousand watts of power during peak sunlight hours.
- Engineers must calculate the total wattage of all connected appliances to ensure the circuit can handle the load without tripping the breaker.

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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.