An episcopal see is, in the original sense, the official seat (in Latin, sedes) of a bishop. This seat, which is also referred to as the bishop's cathedra, is placed in the bishop's principal church, which is therefore called the bishop's cathedral.The Oxford Dictionary of the Christian Church (Oxford University Press 2005, ISBN 978-0-19-280290-3), s.v. see The seat is also called the bishop's throne, especially in the Eastern Orthodox Church.

The term is also used of the town or place where the cathedral is located, giving rise to expressions such as "the episcopal see of Gibraltar".

The bishop's seat is the earliest symbol of bishop's authority, and the word "see" is thus often applied to the area over which the bishop exercises authority. This usually corresponds to a diocese, as in the expression "within the see of Ebbsfleet" and "built within the see of the bishop of Worcester". But it is sometimes given a wider significance, referring for instance to an area under patriarchal authority.