(6) "Trailer" means a detachable load-carrying unit designed to be attached to a coupling at the rear of a semitrailer and capable of support in operation without the truck tractor.

(68) "Trailer" means every vehicle with or without motive power, other than a pole trailer, designed for carrying persons or property and for being drawn by a motor vehicle and so constructed that no part of its weight rests upon the towing vehicle.

"Trailer" means any vehicle operated over the public roads of this state without motive power when the vehicle is designed for carrying persons or property, either partially or wholly, on its own structure and is designed for being drawn by a self-propelled [...]