ground rent

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Rent paid for land to be used chiefly for building.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun law, real estate Rent paid for the land, usually for a long-term lease or in perpetuity, where the land-owner and the owner of improvements are different; the improvements are effectively security for the payment of the rent.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun payment for the right to occupy and improve a piece of land