1 the male head of a family or tribe.
2 (often in pl.) Bibl. any of those regarded as fathers of the human race, esp. the sons of Jacob, or Abraham, Isaac, and Jacob, and their forefathers.
3 Eccl. a the title of a chief bishop, esp. those presiding over the Churches of Antioch, Alexandria, Constantinople, and (formerly) Rome; now also the title of the heads of certain autocephalous Orthodox Churches. b (in the Roman Catholic Church) a bishop ranking next above primates and metropolitans, and immediately below the pope. c the head of a Uniate community.
4 a the founder of an order, science, etc. b a venerable old man. c the oldest member of a group.
Derivatives:
patriarchal adj. patriarchally adv.
Etymology: ME f. OF patriarche f. eccl.L patriarcha f. Gk patriarkhes f. patria family f. pater father + -arkhes -ruler
Useful english dictionary. 2012.