The term 'Monopoly Income' refers to the money a player earns from renting out properties in the board game Monopoly. The two crossword solutions for this term are 'RENTS' (5 letters) and 'RENT' (4 letters). RENTS is the plural form of RENT, which is the money paid by a tenant to a landlord for the use of a property. In the context of Monopoly, RENT is the money that players pay to the owner of a property when they land on it.