Window regulator is the mechanism that raises and lowers the window. For power windows it has the electric motor attached, not sure if you could put the electric motor into a manual ragulator, you may have to get the whole thing. But if you do your shopping at wrecking yards, that's what you will get anyway, the whole regulator.
BTW when replacing a regulator, use rubber door stops to hold the glass up while you pull the regulator out and slip in the new one.