Encyclical

An encyclical was originally a circular letter referenced to all the churches of a specific area in the ancient Roman Church. At that time, the word could be used for a letter target out by any bishop. The word comes from the Late Latin originally from the Latin , a Latinization of Greek ἐνκύκλιος , meaning "circular", "in a circle", or "all-round", also part of the origin of the word encyclopedia.

The term has been used by Catholics, Anglicans as well as the Eastern Orthodox.

Anglican usage

Amongst Anglicans the term encyclical was revived in the gradual 19th century. it is applied to circular letters issued by the English primates.