an elementary particle with negative charge

a unit of potential equal to the potential difference between two points on a conductor carrying a current of 1 ampere when the power dissipated between the two points is 1 watt; equivalent to the potential difference across a resistance of 1 ohm when 1 ampere of current flows through it

a unit of electrical power in an AC circuit equal to the power dissipated when 1 volt produces a current of 1 ampere