Tenn. Code Ann. § 55-1-120: "Gross weight" defined

"Gross weight" means the weight of a vehicle without load, plus the weight of any load thereon, which, more specifically, includes the total weights of a truck or a truck-tractor and a semitrailer, trailer or pole trailer, or any combination of such vehicles, including the load thereon, towed by one (1) vehicle with motive power.