Labor power
Set of physical and intellectual capacities that a person applies when generating use values in a productive process. Its sale for a certain time in the market as a commodity by those who cannot produce by themselves and have no other commodity to sell -the proletariat-, is the basic condition and institution of capitalism.
http://dictionary.marxismo.school/Labor powerBy labor power or labor capacity we understand the set of physical and mental faculties that exist in the corporeality, in the living personality of a human being and that he puts in motion when he produces use values of any kind.
Karl Marx. Capital, 1866.