horsepower
Americannoun
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a foot-pound-second unit of power, equivalent to 550 foot-pounds per second, or 745.7 watts.
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Informal. the capacity to achieve or produce; strength or talent.
The university's history faculty is noted for its intellectual horsepower.
noun
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an fps unit of power, equal to 550 foot-pounds per second (equivalent to 745.7 watts)
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a US standard unit of power, equal to 746 watts
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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
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
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
Given AI’s electricity consumption and chip costs, businesses aren’t going to let their horsepower be diverted by the machines themselves for humanity-destroying side projects, unless maybe the machines can show how humanity-destroying might be profitable.
From The Wall Street Journal • Mar. 29, 2026
There are lots of ways to make horsepower but few sound as pretty.
From The Wall Street Journal • Oct. 23, 2025
The Elettrica boasts 1,000 horsepower and a range of at least 329 miles, but its success hinges on appealing to traditional Ferrari enthusiasts.
From Barron's • Oct. 9, 2025
Marine engines have more horsepower, so it takes more strength to turn the flywheel.
From "Flush" by Carl Hiaasen
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.