Illinois Statutes Chapter 815. Business Transactions § 603/5. Definitions

(a) “Payment application” means, in accordance with the terms and definitions of the applicable contract, any invoice, bill or other request for periodic payment, final payment, payment of change order or request for release of retainage from the contractor to the owner.

(b) “Construction contract” means a contract or subcontract, entered into after the effective date of this Act, for the design, construction, alteration, improvement, or repair of Illinois real property, except for contracts that require the expenditure of public funds and contracts for the design, construction, alteration, improvement, or repair of single family residences or multiple family residences with 12 or fewer units in a single building.

(c) “Contractor” and “subcontractor” shall have the meanings ascribed to them by the Illinois Mechanics Lien Act and cases decided under that Act.