watt-hour

noun

ˈwät-ˈau̇(-ə)r How to pronounce watt-hour (audio)
: a unit of work or energy equivalent to the power of one watt operating for one hour

Examples of watt-hour in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This is good for a modern lithium-ion battery, but far below the company’s claimed 400 watt-hours per kilogram. — Sujita Sinha, Interesting Engineering, 9 June 2026 Southwest says spare batteries and power banks must be carried onboard, with terminals protected against short circuits and capacity capped at 100 watt-hours. — Aidin Vaziri, San Francisco Chronicle, 8 Apr. 2026 Last month, Southwest Airlines also started limiting each customer to one power bank not exceeding 100 watt-hours, requiring they be kept in the cabin and not in the overhead bin. — Alison Fox, Travel + Leisure, 21 May 2026 The Helios Horizon's previous lithium-ion pack delivered 260 Wh/kg (watt-hours per kilogram, a measure of how much energy a battery holds relative to its weight). — Omar Kardoudi june 12, New Atlas, 12 June 2026 See All Example Sentences for watt-hour

Word History

First Known Use

1888, in the meaning defined above

Time Traveler
The first known use of watt-hour was in 1888

Rhymes for watt-hour

See All Rhymes for watt-hour

Browse Nearby Words

Wattevilleite
watt-hour
watt-hour meter
See all Nearby Words

Cite this Entry

“Watt-hour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/watt-hour. Accessed 7 Jul. 2026.

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