- Greek: pyxos, box-tree
A vessel in which the Sacred Host is either preserved or carried. It is made of precious metal, gold or silver, and if made of silver, is usually gold-plated. The pyx, or ciborium, is the ordinary receptacle for the preservation of the Sacred Host in the tabernacle. A smaller pyx is used for carrying the Blessed Sacrament to the sick. This is a small round case and should be gold-plated at least inside. It suffices for from one to four or five hosts.