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horsepower

[ hawrs-pou-er ]
/ ˈhɔrsˌpaʊ ər /
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noun
a foot-pound-second unit of power, equivalent to 550 foot-pounds per second, or 745.7 watts.
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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Origin of horsepower

First recorded in 1800–10; horse + power
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use horsepower in a sentence

British Dictionary definitions for horsepower

horsepower
/ (ˈhɔːsˌpaʊə) /

noun
an fps unit of power, equal to 550 foot-pounds per second (equivalent to 745.7 watts)
a US standard unit of power, equal to 746 watts
Abbreviation: HP, h.p
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for horsepower

horsepower
[ hôrspou′ər ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for horsepower

horsepower

A unit of power equal to about 746 watts.

notes for horsepower

The horsepower is used to measure the power of engines.

notes for horsepower

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.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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