As used in this article, the following words and phrases shall have the following meanings, respectively, unless the context clearly indicates otherwise:
(1) USED LANDS. Lands that are being utilized for the specific and immediate purposes of the state or of any institution or department thereof or by any township or the inhabitants thereof, including buildings, grounds and premises, experiment farms, leased, mined or cultivated property and any other tracts utilized by or for the operation of any institution or department.
(2) UNUSED LANDS. Lands not utilized for the immediate purposes of any institution or department, not being cultivated, leased or mined and not contiguous to the premises of any department or institution or state building.