# horsepower

/ˈhɔɹˌspaʊɝ/ (US) · /hˈɔːspaʊɐ/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/horsepower
Updated: 2026-05-06

## Definition

a unit used to measure the power of an engine. It tells you how much work a car or machine can do in a certain amount of time.

For teachers: a unit of power equal to 550 foot-pounds per second or approximately 746 watts. Often used to quantify the output of internal combustion engines or electric motors.

## Examples

- The new sports car has over 400 horsepower.
- When choosing a tractor, the farmer looked for high horsepower to ensure it could pull heavy machinery across the muddy fields.
- Engineers managed to increase the vehicle's horsepower without sacrificing fuel efficiency by implementing a more sophisticated turbocharging system and reducing the overall weight of the chassis.

## Usage notes

- Usually treated as uncountable when referring to the general power of an engine, though specific figures are often cited as a number followed by the word.

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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.