patriarch

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

• noun A man who rules a family, clan, or tribe.
• noun One of the antediluvian progenitors of the human race, from Adam to Noah.
• noun Abraham, Isaac, Jacob, or any of Jacob's 12 sons, the eponymous progenitors of the 12 tribes of Israel.
• noun Used formerly as a title for the bishops of Rome, Constantinople, Jerusalem, Antioch, and Alexandria.
• noun Roman Catholic Church A bishop who holds the highest episcopal rank after the pope.
• noun Eastern Orthodox Church Any one of the bishops of the sees of Constantinople, Antioch, Alexandria, Moscow, and Jerusalem who has authority over other bishops.
• noun Judaism The head of the Sanhedrin in Syrian Palestine from about 180 BC to AD 429.
• noun Mormon Church A high dignitary of the priesthood empowered to invoke blessings.
• noun One who is regarded as the founder or original head of an enterprise, organization, or tradition.
• noun A very old, venerable man; an elder.
• noun The oldest member of a group.

from The Century Dictionary.

• noun The father and ruler of a family; one who governs by paternal right; specifically, one of the progenitors of the Israelites—Abraham, Isaac, Jacob, and the sons of Jacob; also, one of those Biblical personages who were heads of families before the deluge: the latter are termed antediluvian patriarchs.
• noun Hence In subsequent Jewish history, one of the heads of the Sanhedrim after the destruction of Jerusalem and the dispersion, the patriarch of the Western Jews residing in Palestine, that of the Eastern in Babylon.
• noun In the early church, and in the Orthodox Greek and other Oriental churches, a bishop of the highest rank; in the Roman Catholic Church, a bishop of the highest rank next after the Pope.
• noun One of the highest dignitaries in the Mormon Church, who pronounces the blessing of the church. Also called evangelist.
• noun A venerable old man; hence, figuratively, any object of patriarchal or venerable aspect.

from the GNU version of the Collaborative International Dictionary of English.

• noun The father and ruler of a family; one who governs his family or descendants by paternal right; -- usually applied to heads of families in ancient history, especially in Biblical and Jewish history to those who lived before the time of Moses.
• noun (R. C. Ch. & Gr. Ch.) A dignitary superior to the order of archbishops.
• noun A venerable old man; an elder. Also used figuratively.

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

• noun An old leader of a village or community.
• noun The male head of a tribal line or family.

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

• noun the male head of family or tribe
• noun a man who is older and higher in rank than yourself
• noun any of the early biblical characters regarded as fathers of the human race
• noun title for the heads of the Eastern Orthodox Churches (in Istanbul and Alexandria and Moscow and Jerusalem)