Catholicon

A Catholicon is a comprehensive encyclopedia or dictionary of the Catholic Church, its doctrines, practices, and history. The term originates from the Greek word "katholikos," meaning universal, reflecting the encyclopedic scope of the work. The first Catholicon was compiled by the Byzantine scholar Photios I in the 9th century, during the reign of Emperor Michael III. Photios' work, known as the Bibliotheca, was a vast collection of information on various subjects, including theology, philosophy, and history, with a particular focus on the Church.

The Bibliotheca was later expanded and revised by other scholars, such as Constantine Porphyrogennetos and John Tzetzes, who added more entries and updated the existing ones. The Catholicon became an essential reference work for scholars and theologians in the Byzantine Empire and beyond, providing a wealth of information on the Church's teachings, rituals, and practices.

Over time, the term "Catholicon" came to refer specifically to encyclopedic works on the Catholic Church, rather than the broader sense of a comprehensive collection of knowledge. Today, the term is used to describe any encyclopedia or dictionary that focuses on the Catholic Church and its teachings. Some notable examples of modern Catholicons include the Catholic Encyclopedia, published by the Catholic University of America, and the Catholic Dictionary, published by the Catholic Truth Society. These works continue the tradition of providing a comprehensive and authoritative reference on the Catholic Church and its doctrines.