Conductor /(kŏn*dŭk"tẽr)/

Con·duct·or

Conductor

n.
  1. One who, or that which, conducts; a leader; a commander; a guide; a manager; a director.
    Zeal, the blind conductor of the will.
  2. One in charge of a public conveyance, as of a railroad train or a street car. [U. S.]
  3. The leader or director of an orchestra or chorus. (Mus.)
  4. A substance or body capable of being a medium for the transmission of certain forces, esp. heat or electricity; specifically, a lightning rod. (Physics)
  5. A grooved sound or staff used for directing instruments, as lithontriptic forceps, etc.; a director. (Surg.)
  6. Same as Leader. (Arch.)

Phrases & Compounds
Prime conductor
the largest conductor of an electrical machine, serving to collect, accumulate, or retain the electricity.