In the Roman Catholic Church, it is "the authority, privilege, or permission, to perform an act or function. In a broad sense, a faculty is a certain power, whether based on one's own right, or received as a favour from another, of validly or lawfully doing some action. The most common use of the term is in the context of 'priestly faculties', which is the permission given to a priest by his diocesan bishop or religious superior, legally permitting him to perform the Sacraments. Normally, a priest's faculties only permit him to celebrate within his own diocese or religious order.
In the Church of England (whose canons have the status of national law) the "faculty jurisdiction" is set out in the Care of Churches and Ecclesiastical Jurisdiction Measure 1991, and the Faculty Jurisdiction Rules 2000.