Praesanctificatio is in the Roman Catholic Church the mass celebrated on Green-Thursday, when two hosts are consecrated, whereof the priest tastes one at the communion, reserving the other for the next day, when the missa praesanctificatorum is to be solemnized. In the Greek Church missapraesanctificatorum (mass of the loaves blessed in advance) is the mass celebrated on the Wednesdays and Fridays of Lent; it consists in the communion of the holy elements which have been consecrated on the preceding Sundays. SEE MASS. See Siegel, Christliche Alterthümer (Index in vol. 4).