When used in this Article:
"Authority" means any Metropolitan Exposition, Auditorium and Office Building Authority, as provided in this Article.
"Board" means the governing and administrative body of any Metropolitan Exposition, Auditorium and Office Building Authority, as provided in this Article.
"Metropolitan area" means all that territory in the State of Illinois lying within the corporate boundaries of the county or counties establishing an authority as provided in this Article.
70 ILCS 200/170-5