consuetudinary

Etymology
From, from. .

Noun

 * 1) A ritual book containing the forms and ceremonies used in the services of a particular monastery, cathedral or religious order.
 * 2) An unwritten law established by usage, derived by immemorial custom from antiquity.
 * 1) An unwritten law established by usage, derived by immemorial custom from antiquity.

Adjective

 * 1)  Customary; considered law by virtue of the fact that it is generally observed.