What is Ecclesiastical Law?

Legal Definition
By this phrase it is intended to include all those rules which govern ecclesiastical tribunals. Vide Law Canon.
-- Bouviers Law Dictionary
Legal Definition
The body of jurisprudence administered by the ecclesiastical courts of England; derived, in large measure, from the canon and civil law. As now restricted, it applies mainly to the affairs, and the doctrine, discipline, and worship, of the established church. De Witt v. De Witt, 67 Ohio St. 340, 66 N. El 136.
-- Black's Law Dictionary
Legal Definition
The law enforced in the ecclesiastical courts.
-- Ballentine's Law Dictionary