For the purposes of this chapter, unless the context otherwise requires:
(1) "Department" means the department of licensing.
(2) "Motor vehicle" means all motor vehicles, trailers and semitrailers used, or of the type designed primarily to be used, upon the public streets and highways, for the convenience or pleasure of the owner, or for the conveyance, for hire or otherwise, of persons or property, including fixed loads and facilities for human habitation; but shall not include (a) vehicles carrying exempt licenses, (b) dock and warehouse tractors and their cars or trailers, lumber carriers of the type known as spiders, and all other automotive equipment not designed primarily for use upon public streets, or highways, (c) motor vehicles or their trailers used entirely upon private property, (d) mobile homes and travel trailers as defined in RCW 82.50.010, or (e) motor vehicles owned by nonresident military personnel of the armed forces of the United States stationed in the state of Washington provided personnel were also nonresident at the time of their entry into military service.
(3) "Truck-type power or trailing unit" means any vehicle that is subject to the fees under RCW 46.17.355, except vehicles with an unladen weight of six thousand pounds or less, RCW 46.16A.425, 46.17.335, or 46.17.350(1)(c).