As used in this chapter, the following words and phrases shall have the meanings ascribed herein unless the context in which used dictates otherwise:
(1) “Commissioner” means the commissioner of revenue, or the commissioner's authorized delegate;
(2) “Department” means the department of revenue;
(3) “Inspector” means an employee of the petroleum tax division of the department who is designated as such; and
(4) “Oil or substance” means any oil or substance described in §§ 60-3-103 and 60-3-104.