A quantity of labor reckoned in units of time.(noun)
The Century Dictionary (Public Domain)
Use "labor-time" in a sentence
"Raising the value of basic necessities effectively lowers wages, but this does not change the value of those commodities (whether expressed in labor-time, money, or even grain)."
"This would imply to me that there is some multiplier, or, putting it another way, that there is or ought to be the concept of simple labor-time, in which exchange value is expressed."
"Other forms of labor (ie, with a machine that multiplies the efficiency of labor, or with highly skilled labor) could then be expressed in terms of simple labor-time."