Anointing of the Sick is the ritual anointing of a sick person and is a Sacrament of the Catholic Church. It is also described, using the more archaic synonym "unction" in place of "anointing", as unction of the sick.The Council of Trent (Sess. XIV, cap. i, De Extr. Unct.) in an English translation quoted in Catholic Encyclopedia; the Coptic Church ( Sacrament of Unction of the Sick); Old Catholic Church ( Unction of the Sick); etc. Administration to the sick is used by some Churches. Community of Christ: The SacramentsThe early-twentieth-century Catholic Encyclopedia states: "In previous ages the sacrament was known by a variety of names, e.g., the holy oil, or unction, of the sick; the unction or blessing of consecrated oil; the unction of God; the office of the unction; etc. In the Eastern Church the later technical name is euchelaion (i.e. prayer-oil); but other names have been and still are in use, e.g. elaion hagion (holy), or hegismenon (consecrated), elaion, elaiou Chrisis,
Source:
http://en.wikipedia.org/wiki/Extreme Unction