Holy See

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

• noun The see of the bishop of Rome.
• noun The authority, jurisdiction, and governmental functions associated with the papacy.

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

• proper noun The episcopal jurisdiction of the Bishop of Rome, commonly known as the Pope. It is the preeminent see of the Catholic Church. It is also the sovereign entity headed by the Pope which governs the Vatican and represents the Catholic Church in temporal affairs.

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

• noun the smallest sovereign state in the world; the see of the Pope (as the Bishop of Rome); home of the Pope and the central administration of the Roman Catholic Church; achieved independence from Italy in 1929