Gratian’s decree, or deeretum. A collection of ecclesiastical
law in three books or parts, made in the year 1151, by Gratian, a Benedictine monk of
Bologna, being the oldest as well as the first in order of the collections which together
form the body of the Roman canon law. 1 Bl. Comm. 82; 1 Reeve, Eng. Law, 07.