In this part, the following definitions apply unless the context indicates otherwise:
(1) "Agency" includes:
(a) all offices, departments, divisions, boards, commissions, councils, committees, institutions, university units, political subdivisions, and other entities or instrumentalities of this state government;
(b) with respect to delinquent taxes that the department is requested to collect, state and local entities whose personal property taxes are collected by the county treasurer; and
(c) the federal internal revenue service.
(2) "Department" means the department of revenue provided for in 2-15-1301.