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[wot-ouuh r, -ou-er] /ˈwɒtˌaʊər, -ˌaʊ ər/
a unit of energy equal to the energy of one watt operating for one hour, equivalent to 3600 joules.
Abbreviation: Wh.
Origin of watt-hour
1885-90 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for watt-hour
  • Per watt-hour, the materials cost the same as other lithium-iron-phosphate electrode materials, he says.
  • Every utility shall install such watt-hour meters as necessary to obtain a record of output of its generating station or stations.
  • The watt-hour constant for the meter itself shall be shown on all watt-hour meters.
British Dictionary definitions for watt-hour


a unit of energy equal to a power of one watt operating for one hour. 1 watt-hour equals 3600 joules
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
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watt-hour in Science
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.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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