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watt

unit of measurement
Also known as: W
Written and fact-checked by
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Out with Romo, in with Watt: CBS Sports makes major NFL broadcast change • Oct. 22, 2026, 2:55 PM ET (San Antonio Express-News)

watt, unit of power in the International System of Units (SI) equal to one joule of work performed per second, or to 1/746 horsepower. An equivalent is the power dissipated in an electrical conductor carrying one ampere current between points at one volt potential difference. It is named in honour of James Watt, British engineer and inventor. One thousand watts equal one kilowatt. Most electrical devices are rated in watts.