Pyx

A pyx or pix (Latin: pyxis, transliteration of Greek: πυξίς, boxwood receptacle, from πύξος, box tree) is a small round container used in the Catholic, Old Catholic and Anglican Churches to carry the consecrated host (Eucharist), to the sick or those otherwise unable to come to a church in order to receive Holy Communion. The term can also be used in archaeology and art history to describe small round lidded boxes designed for any purpose from antiquity or the Middle Ages, such as those used to hold coins for the Trial of the Pyx in England.

The word "pyx" comes from the Greek word πυξίς, "pyxis" meaning box or receptacle. The plural is pyxides. While the word may be applied to any covered carrier, in the modern usage the term is usually applied to small, flat, clamshell-style containers often about the size of a pocket watch and usually made of brass or other metals, traditionally lined with gold. A fabric or leather pouch in which the pyx may be carried is known as a burse. Typically, this kind of burse can be securely closed and is fixed with cords so that the priest, deacon, or extraordinary minister of Holy Communion can affix it to his or her person during transport to prevent the consecrated host(s) from being accidentally lost.

The term pyx is also a standard term used in the Catholic Church to refer to a flat, circular container, sometimes called a lunette, composed of a ring of metal (usually lined with gold) holding two glass or crystal disks, to create a round, flat, glass-enclosed space for the Eucharistic Host. This is used together with a monstrance for exposition and Benediction services. The lunette is often kept in another object, itself sometimes called a pyx, luna, or custodia, which is usually a round box often on a small stand, giving the impression of a faceless, old-fashioned, alarm clock.

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