Joule n. : A unit of work which is equal to 107 units of work in the C. G. S. system of units (ergs), and is practically equivalent to the energy expended in one second by an electric current of one ampere in a resistance of one ohm. One joule is approximately equal to 0.738 foot pounds.

Example:
Where does the missing Joule go in this inelastic collision?

Taxonomy
joule, energy, calories, James Prescott Joule, relationship, symbol, free encyclopedia, volt, thermochemical, MJ, newton, watt, kinetic energy, unit of energy, food calories, gram, GJ, hundredth.

Defination from the web:
joule is defined as the amount of work done by a force of one newton moving an object through a distance of one metre. Other relationships are: ... This SI unit is named after James Prescott Joule. ...