(a) In this chapter:
(1) "Board" means the board of the Texas Department of Motor Vehicles.
(2) "Department" means the Texas Department of Motor Vehicles.
(3) "Purchaser" and "seller" have the meanings assigned by Section 501.002.
(b) A word or phrase that is not defined by this chapter but is defined by Section 502.001 has the meaning in this chapter that is assigned by that section.