Labor power (n.) is that which the working man sells to the capitalist. It is that whose temporary disposal he makes over to the capitalist. Slavery is just such a sale whose time comprises a lifetime.
Labor power (n.) is the total mental and physical capabilities that lie in the human body and personality which are put into motion whenever man produces something.
Labor power (n.) cannot be stored in warehouses after the capitalist has bought it, as he may do with the raw material.
Labor power's (n.) value is the value of the means of subsistence necessary for the maintenance of its owner.
Labor power (n.) is the vantage from which tailoring and weaving equivalent in that they are both a productive expenditure of human brains, muscles, nerves, hands.