one of the major representative groups of classical Protestantism that arose in the 16th-century Reformation. Generally speaking, the modern Presbyterian churches trace their origins to the Calvinist churches of the British Isles, the Continental counterparts of which came to be known by the more inclusive designation Reformed. The term presbyterian denotes a collegiate type of church government by pastors and lay leaders called elders, or presbyters. Strictly speaking, all Presbyterian churches are a part of the Reformed, or Calvinist, tradition, although not all Reformed churches are presbyterian in their form of government.

The Reformed and Presbyterian churches are treated jointly in Reformed and Presbyterian churches. The presbyterian form of church government and the histories of respective Presbyterian churches (e.g., Presbyterian Church 【U.S.A.】 (Presbyterian Church (U.S.A.)); Church of Scotland (Scotland, Church of)) are treated individually. See also Calvinism.