SACRISTY (through Fr. sacristie, from med. Lat. sacristia or sacristina), the term in ecclesiastical architecture given to the room or hall in a large church wherein are kept the vestments and utensils (sacra) used in the services and celebrations. Like the diaconicou in the Greek Church, it was usually situated on the north side of the chancel, but its position varies according to that of the chapter-house, as it is generally placed between the latter and the church.