Conciliar

Conciliar is an adjective meaning related to a council or to the authority of a council. It derives from Latin conciliālis, from concilium, meaning a council or assembly. In religious and historical contexts, conciliar is often attached to the idea of governance by councils rather than by a single ruler or pope.

A prominent historical use is in conciliarism, a movement within the Christian church that argued ecumenical councils could have authority over the pope and church governance. Conciliarism emerged during the late medieval period, notably around the Western Schism, and gained momentum in the 15th century with councils such as Basel and Constance. The movement sought reform through collective council action, but its influence waned as papal authority was reaffirmed, particularly after the Council of Trent (1545–1563).

In modern usage, conciliar can describe any body or process governed by a council. A conciliar approach emphasizes deliberation, consensus, and decision-making by a council rather than by a single executive. The term is most common in historical or ecclesiastical writing, though it can appear in political or organizational theory to describe council-based governance.

See also terms include conciliarism and conciliar movement, and broader discussions of council-based governance. The word remains relatively rare in everyday English, but it appears in scholarly and historical contexts dealing with church history, governance, and constitutional theory.