Cite
 

Meaning of horsepower-hour

horse•pow•er-hour

Pronunciation: (hôrs'pou"ur-our", -ou"ur), [key]
— n.
  1. a foot-pound-second unit of energy or work, equal to the work done by a mechanism with a power output of one horsepower over a period of one hour.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.