watt-hour

or watt·hour

[ wot-ouuhr, -ou-er ]

noun

1. a unit of energy equal to the energy of one watt operating for one hour, equivalent to 3600 joules. : Wh

watt-hour

noun

1. a unit of energy equal to a power of one watt operating for one hour. 1 watt-hour equals 3600 joules

watt-hour

1. A unit of energy, especially electrical energy, equal to the work done by one watt acting for one hour. It is equivalent to 3,600 joules.

Word History and Origins

Origin of watt-hour¹

First recorded in 1885–90

Example Sentences

A watt-hour is the amount of energy needed by a device which uses one watt and is operated for one hour.

From Project Gutenberg

Electricity is usually purchased by the kilowatt hour, and measured by the watt-hour meter (Fig. 160).

From Project Gutenberg