a person who conducts; a leader, guide, director, or manager.

an employee on a bus, train, or other public conveyance, who is in charge of the conveyance and its passengers, collects fares or tickets, etc.

a person who directs an orchestra or chorus, communicating to the performers by motions of a baton or the hands his or her interpretation of the music.

a substance, body, or device that readily conducts heat, electricity, sound, etc.

Copper is a good conductor of electricity.

lightning rod.

noun

director , guide , maestro , manager , marshal , master , supervisor , escort , lead , leader , pilot , shepherd , usher , aqueduct , bandleader , cathode , cicerone , collector , convoy , copper , guard , impresario , material , motorman , propagator , transmitter