reserve clause

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

• noun A clause formerly included in the contract of a professional athlete that allowed the automatic extension of the contract for a year beyond its expiration, thus binding the player to the organization until release, retirement, or a trade.

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

• noun a clause that used to be part of the contract with a professional athlete extending the contract for a year beyond its expiration