Piscina
A piscina is a shallow basin placed near the altar of a church, or else in the vestry or sacristy, used for washing the communion vessels. The sacrarium is the drain itself. Anglicans usually refer to the basin, calling it a piscina. Roman Catholics usually refer to the drain, and by extension, the basin, as the sacrarium. They are often made of stone and fitted with a drain, and are in some cases used to dispose of materials used in the sacraments and water from liturgical ablutions. They are found in Roman Catholic, Anglican, and Lutheran churches, and a similar vessel is used in Eastern Orthodox churches.