The wattmeter is an instrument for measuring the electric power (or the supply rate of electrical energy) in watts of any given circuit. Electromagnetic wattmeters are used for measurement of utility frequency and audio frequency power; other types are required for radio frequency measurements. ==Electrodynamic== The traditional analog wattmeter i... Found on http://en.wikipedia.org/wiki/Wattmeter
Watt'me`ter noun [ Watt + meter .] (Physics) An instrument for measuring power in watts, -- much used in measuring the energy of an electric current. Found on http://www.encyclo.co.uk/webster/W/16