season ticket

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

• noun A ticket valid for a specified period of time, as for a series of performances or for transportation between designated points.

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

• noun A ticket that is valid for all of the events in a series of related events for which individual tickets would otherwise be needed.

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

• noun a ticket good for several trips or to attend a season of entertainments; sold at a reduced rate