Definition of horsepower
1 : the power that a horse exerts in pulling
2 : a unit of power equal in the U.S. to 746 watts and nearly equivalent to the English gravitational unit of the same name that equals 550 foot-pounds of work per second
3 : effective power
intellectual horsepower computing horsepower
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Time Traveler for horsepower
The first known use of horsepower was in 1806
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