35 ILCS 5/102: Construction.

Except as otherwise expressly provided or clearly appearing from the context, any term used in this Act shall have the same meaning as when used in a comparable context in the United States Internal Revenue Code of 1954 or any successor law or laws relating to federal income taxes and other provisions of the statutes of the United States relating to federal income taxes as such Code, laws and statutes are in effect for the taxable year.