horsepower

American  

[hawrs-pou-er] / ˈhɔrsˌpaʊ ər /

noun

1. a foot-pound-second unit of power, equivalent to 550 foot-pounds per second, or 745.7 watts.

2. Informal. the capacity to achieve or produce; strength or talent.

   The university's history faculty is noted for its intellectual horsepower.

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horsepower British  

/ ˈhɔːsˌpaʊə /

noun

1. an fps unit of power, equal to 550 foot-pounds per second (equivalent to 745.7 watts)

2. a US standard unit of power, equal to 746 watts

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horsepower Scientific  

/ hôrs′pou′ər /

1. A unit that is used to measure the power of engines and motors. One unit of horsepower is equal to the power needed to lift 550 pounds one foot in one second. This unit has been widely replaced by the watt in scientific usage; one horsepower is equal to 745.7 watts.

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horsepower Cultural  

1. A unit of power equal to about 746 watts.

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Discover More

The horsepower is used to measure the power of engines.

This term was coined by James Watt, who invented a new type of steam engine in the eighteenth century. Watt found that the horse could do a certain amount of work per second; when he sold his steam engines, this measurement allowed him to estimate the worth of an engine in terms of the number of horses it would replace. Therefore, a six-horsepower engine was capable of replacing six horses.

Etymology

Origin of horsepower

First recorded in 1800–10; horse + power

Compare meaning

How does horsepower compare to similar and commonly confused words? Explore the most common comparisons:

• brake horsepower vs. horsepower

Example Sentences

"What we've done is taken two of our 74 horsepower engines from our construction machines, we've laid them on their side and we've turned the power up," Lee Harper, chief engineer at JCB, explained.

From BBC • Jun. 1, 2026

Demand may also need time to catch up with that extra datacenter horsepower, while macro cycles are still an important consideration.

From MarketWatch • May 28, 2026

Three axial flux motors are capable of delivering 1,153 horsepower and are also capable of going from zero to 60 miles per hour in about two seconds.

From Barron's • May 20, 2026

The vehicle is a hybrid convertible powered by a twin-turbo 3.0-liter V6 and an electric motor, producing a combined 819 horsepower.

From Los Angeles Times • Apr. 22, 2026

Marine engines have more horsepower, so it takes more strength to turn the flywheel.

From "Flush" by Carl Hiaasen

Related Words

• dynamism
• electricity
• heat
• potential
• service
• strength