Adjective
(sports) Of a sportsman's clause or contract: guaranteeing that they will not be taken off the team during a designated period.
(sports) Of a sporting activity (in a school, etc.): allowing an unlimited number of participants, rather than members of a fixed-size team who must "make the cut".
(business, by extension) Of any clause or contract: remaining in force until it expires, without the possibility of earlier cancellation.
Source: en.wiktionary.org