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.
So when engine-maker Mercury Marine showed him an outboard motor that generates more horsepower than a Ferrari Portofino, he wanted four.
From The Wall Street Journal ● Jul. 27, 2026
“We want to make sure that however high in horsepower we go, we still make the product affordable, with enough volume to drive some level of scale,” he said.
From The Wall Street Journal ● Jul. 27, 2026
He said the finished car would have about 1,600 horsepower in total.
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
A man sat on top of the horsepower, and when everything was ready he clucked to the horses, and they began to go.
From "Little House in the Big Woods" by Laura Ingalls Wilder
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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.