In Christian church architecture: 1. A room near the altar area in which liturgical vessels and vestments are kept and prepared. 2. An area where clergy wait or prepare for the worship service. The sacristy is an area outside the public area of the chancel, usually including countertops and running water for preparation of communion items before the service begins. The sacristy may also function as a vestry (place where vestments are donned by clergy), but sometimes there is an additional vestry, especially for servers and choir members. (= diaconikon in Greek Orthodox churches)
A sacrist usually has charge of the sacred vessels used in worship. Often the job is expanded to ordering much of the furnishings in a cathedral. A sacristy is a room annexed to a cathedral where the sacred vessels are stored.
From the Latin sacristia, meaning "holy things." The room where the communion vessels and paraments are kept. The vestments for pastor and liturgical assistants may also kept here or in a separate room, the vestry.
A sacristy is a room for keeping vestments (such as the cassock and chasuble) and other church furnishings, sacred vessels, and church treasures. The sacristy is usually located inside the church, but it could be an annex or separate building (as in some monasteries). In most older churches the sacristy is near one of the side altars or more usually behind or to the side of the main altar.