Confessio

(from the article `Patrick, Saint`) The best known passage in the Confessio, his spiritual autobiography, tells of a dream, after his return to Britain, in which one Victoricus ... A 9th-century record, the Book of Armagh, includes a work by Patrick himself, the Confessio (`Confession,` a reply to charges made by British ... ...
Found on http://www.britannica.com/eb/a-z/c/126

Confessio

A niche for relics located near the altar.
Found on http://www.britainexpress.com/History/medieval/church-glossary.htm

confessio

A type of crypt which consists of a series of linked passages. The most famous confessio crypt during the Middle Ages was that of Old Saint Peter's church in Rome, which contained the tomb os Saint Peter.
Found on http://www.pitt.edu/~medart/menuglossary/INDEX.HTM
No exact match found