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• watt
  watt

  noun

  the standard unit of power in the International System of Units (SI), equivalent to one joule per second and equal to the power in a circuit in which a current of one ampere flows across a potential difference of one volt. W, w.
• Watt
  Watt

  noun

  James, 1736–1819, Scottish engineer and inventor.

watt

¹ American  

[wot] / wɒt /

noun

• watts
  plural

1. the standard unit of power in the International System of Units (SI), equivalent to one joule per second and equal to the power in a circuit in which a current of one ampere flows across a potential difference of one volt. W, w.

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Watt ² American  

[wot] / wɒt /

noun

1. James, 1736–1819, Scottish engineer and inventor.

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Watt ¹ British  

/ wɒt /

noun

1. James. 1736–1819, Scottish engineer and inventor. His fundamental improvements to the steam engine led to the widespread use of steam power in industry

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watt ² British  

/ wɒt /

noun

1.  W.  the derived SI unit of power, equal to 1 joule per second; the power dissipated by a current of 1 ampere flowing across a potential difference of 1 volt. 1 watt is equivalent to 1.341 × 10 ^–3 horsepower

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watt ¹ Scientific  

/ wŏt /

1. The SI derived unit used to measure power, equal to one joule per second. In electricity, a watt is equal to current (in amperes) multiplied by voltage (in volts).

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Watt ² Scientific  

1. British engineer and inventor who patented a much improved version of the steam engine (1769) and devised the unit of horsepower. The watt unit of power is named for him.

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watt Cultural  

1. The basic unit of power, named after the eighteenth-century Scottish inventor James Watt.

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Other Word Forms

Noun Inflected Forms

• watts
  plural

Etymology

Origin of watt

First recorded in 1882; named after J. Watt

Example Sentences

See Examples For:

watt Watt watts

With the highest thread density, the chips can support more AI agents per watt, per dollar and per chip rack, according to the company.

From MarketWatch ● Jul. 23, 2026

Early tests show that the chip will deliver performance per watt “substantially better” than current state-of-the-art chips, they added.

From The Wall Street Journal ● Jun. 24, 2026

Measurements revealed a responsivity of 2.7 amperes per watt.

From Science Daily ● May 31, 2026

Nvidia said the deployment of its CPUs will improve performance per watt in Meta’s data centers, a key efficiency metric for inference.

From Barron's ● Feb. 18, 2026

Modern radio telescopes are exquisitely sensitive; a distant quasar is so faint that its detected radiation amounts perhaps to a quadrillionth of a watt.

From "Cosmos" by Carl Sagan

Then in 1781 James Watt patented a rotary steam engine that could turn a shaft and thus power a factory.

From The Wall Street Journal ● Aug. 2, 2026

Watt — have won the NFL’s defensive player of the year award three times.

From Los Angeles Times ● Jul. 26, 2026

Thanks largely to the trade deal, about 85% of American imports from Canada were tariff-free last year, Watt said.

From The Wall Street Journal ● Jul. 22, 2026

Watt stepped down as chief executive of the brand in 2024 to become its "captain and co-founder".

From BBC ● Jul. 17, 2026

By 1800 only 2,200 steam engines had been built in Britain, some two thirds of which were Newcomen engines, and a quarter Boulton and Watt engines.

From "The Invention of Science" by David Wootton

"Lu-An" has some 2,000 plastic cylinders of soil and compost to give 100 watts of output, enough to power a rice cooker and other appliances.

From Barron's ● Aug. 5, 2026

Doubling the system’s total solar capacity to 1,600 watts would cost an additional $1,000 or so, but in most states, plug-in solar is limited to a maximum output to the home of 1,200 watts.

From The Wall Street Journal ● Jun. 5, 2026

Bikes that do not use pedals, have more than 750 watts of power, or can reach speeds higher than 28 mph are considered electric motorcycles.

From Los Angeles Times ● May 12, 2026

Each spacecraft loses about 4 watts of power every year.

From Science Daily ● May 4, 2026

According to the specs, the heating equipment soaks up 400 watts.

From "The Martian" by Andy Weir