(a) Vehicular crossings. Bridges and tunnels (including plazas and approaches) under the jurisdiction of the Triborough Bridge and Tunnel Authority.

(b) Roadway. That part of bridges, tunnels, plazas and approaches designed for the use of vehicles.

(c) Vehicle. That in or on which anything is carried or a contrivance fitted with wheels.

(d) Motorcycle. Includes all motor-operated vehicles of the bicycle or tricycle type.

(e) Passenger auto. Includes every type of motor-driven vehicle used for the transportation of passengers and registered as such, including taxicabs and cars rented for hire, but excluding buses.

(f) Bus. Includes all motor vehicles used for the transportation of 10 or more persons, including operator.

(g) Truck. Any motor-driven vehicle operated on a public highway, except those classified as buses, taxicabs, passenger autos, tractors and trailers or semitrailers as defined herein.

(h) Tractor. A motor-driven vehicle designed for drawing other vehicles but having no provision for carrying loads independently.

(i) Trailer and semitrailer. A vehicle without motive power drawn by a motor-driven vehicle.

(j) Operator. The driver or any person who pushes, draws, propels, operates or is in charge of a vehicle.

(k) Parking. The standing or waiting on any roadway of any vehicle not actually engaged in taking up or setting down passengers or property. This definition does not apply to disabled vehicles.