The following words and phrases when used in this article shall have the meanings given to them in this section unless the context clearly indicates otherwise:
"Board." The Board of Finance and Revenue.
"Department." The Department of Revenue of the Commonwealth.
"Party." The term includes both a taxpayer and the department.
"Petitioner." A taxpayer.
"Return." The term includes a tax report.
"Secretary." The Secretary of Revenue of the Commonwealth.
72 P.S. § 9701