35 Ill. Adm. Code 204.1610
Definitions
Section 204.1610 Definitions
For the purposes of this Subpart, the definitions in
Sections 204.1620 through 204.1780 apply. When a term is not defined in these Sections,
it shall have the meaning given in this Part, 35 Ill. Adm. Code 211, or the CAA.