an electrically driven public-transport vehicle that does not run on rails but takes its power from an overhead wire through a trolley
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In parallel to the fully mobile bus, was use of the trolleybus.
Encyclopedia Article for trolleybus
trackless trolley
vehicle operated on the streets on rubber tires and powered by electricity drawn from two overhead wires by trolley poles. It is distinct from a trolley car, which runs on rails rather than on tires and is thus a form of streetcar.
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