Haw. Code R. § 19-107-2
As used in this chapter, unless the context clearly indicates otherwise:
"County" means the county of Hawaii, the city and county of Honolulu, the county of Kauai, or the county of Maui, as appropriate.
"Customarily used" means a commonly used mode and that a semitrailer or trailer shall be treated as customarily used in connection with a highway motor vehicle if the vehicle is equipped to tow such semitrailer or trailer.
"Director" means the director of the State department of transportation or his duly authorized representative.
"Federal heavy vehicle use tax" or "FHVU tax" means the use tax imposed by section 4481 of the Internal Revenue Code of 1954, as amended.
"Highway motor vehicle" means any truck or bus that is propelled by its own motor and is designed to carry a load over public highways.
"Net weight" of a vehicle means the actual weight of the vehicle, as used for motor vehicle registration purpose.
"Semitrailer" means a trailer so constructed that a substantial part of its weight rests upon the truck-tractor by which it is drawn.
"State" means the State of Hawaii.
"Trailer" means a vehicle designed for carrying persons or property and for being drawn by a motor vehicle.
"Truck" means a motor vehicle designed, used, or maintained primarily for the transportation of property.
"Truck-tractor" means a truck designed and used primarily for drawing other vehicles and not so constructed as to carry a load to other than a part of the weight of the vehicle and load so drawn.
"Vehicle" means every device in, upon, or by which any person or property is or may be transported or drawn upon a highway, but excludes devices moved by human power or devices used exclusively upon stationary rails or tracks and mopeds.
Haw. Code R. § 19-107-2