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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

Measurements revealed a responsivity of 2.7 amperes per watt.

From Science Daily • May 31, 2026

Ayar Labs says its interconnection chips can provide between four and 20 times the computing throughput per watt of energy spent to power an AI processor, compared with chips that use copper interconnects.

From The Wall Street Journal • Mar. 3, 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

The Vera Rubin “platform,” as Nvidia calls it, consists of six chips, including the Vera central processing unit, which Huang said delivers twice the performance per watt “of the world’s most advanced CPUs.”

From MarketWatch • Jan. 5, 2026

When he has to step over a rope or an air-tnbe on deck, it is hard work—like climbing a watt.

From "The Once and Future King" by T. H. White