Annotinum Pascha
Annotinum Pascha a festival celebrated, according to some. authorities, on the day following the octave of Easter. It is placed on the Thursday before Ascension-day in an ancient ritual of Vienne; but later authorities mention it as having been celebrated on various days, as on the Saturday after Easter-day.
As to the meaning of the expression there are various opinions. Several of the older authorities supposed it to be the anniversary of the Easter of the preceding year. If this anniversary was specially observed, when it fell in the Lent of the actual year it would naturally be omitted or transferred to a period when the fast was over. Probably, however, Annotinum Pascha is a term equivalent to anniversary Pascha; and it is so called because in olden times at Rome those who had been baptized at Easter celebrated the anniversary of their baptism in the next year by solemn services. To this calling to mind of baptismal vows the collects of the Gregorian sacramentary for the day refer. It had become obsolete before 1100.