Unless specifically defined in the Texas Clean Air Act (TCAA) or in the rules of the commission, the terms used in this division have the meanings commonly ascribed to them in the field of air pollution control. In addition to the terms which are defined by the TCAA and §§3.2, 101.1, and 114.1 of this title (relating to Definitions), the following words and terms, when used in this division shall have the following meanings, unless the context clearly indicates otherwise.(1) First sale--Has the meaning as defined under Texas Transportation Code, §501.002.(2) Lease--The use and control of a new light-duty motor vehicle in accordance with a rental contract for a term of 12 consecutive months or more.(3) Lessee--A person who enters into a lease for a new light-duty motor vehicle.(4) Light-duty motor vehicle--A motor vehicle with a gross vehicle weight rating of 10,000 pounds or less.(5) Motor vehicle--A self-propelled device designed for transporting persons or property on a public highway that is required to be registered under Texas Transportation Code, Chapter 502.(6) New light-duty motor vehicle--A light-duty motor vehicle that has never been the subject of a first sale.