From Latin unctionem "anointing." The term unction generally refers to annointment, yet in some groups is also refers to the rite of eucharist or communion in which blessed food and drink are prepared and consumed.
"Every Gnostic Unction in whatever cult or belief, sect or religion, is associated, intimately united with the Last Supper of the Adorable one through the blood pact. The Holy Primeval Christian Gnostic Church, to which we have the privilege of belonging, preserves in secrecy the primeval rituals used by the Apostles. These were the rituals of the Christians that met in the catacombs of Rome during the time of the Caesar Nero. These are the rituals of the Essenes, a humble cast of great initiates to which Jesus the Christ belonged. These are the primeval rituals of the ancient Christians." —Samael Aun Weor, The Perfect Matrimony