Corpus Christi (Latin for Body of Christ) is a Latin Rite solemnity, now designated the solemnity of The Most Holy Body and Blood of Christ (Corpus Christi). It is also celebrated in some Anglican, Lutheran and Old Catholic Churches. Like Trinity Sunday and the Solemnity of Christ the King, it does not commemorate a particular event in Jesus' life. Instead it celebrates the Body and Blood of Christ really present in the Eucharist. Its date is the Thursday after Trinity Sunday, but "where the Solemnity of the Most Holy Body and Blood of Christ is not a Holyday of Obligation, it is assigned to the Sunday after the Most Holy Trinity as its proper day".
(... from Wikipedia on 2012-04-17 13:58:41)