the Christian monogram, consisting of the Greek letters Chi and Rho (XP = Chr{ist}).
monogram made up of the Greek letters Chi and Rho, which look to us like X and P. These letters make up the start of the name of Christ in Greek.
A Christogram is a monogram or combination of letters which forms an abbreviation for the name of Jesus Christ, and is traditionally used as a Christian symbol. Different types of Christograms are associated with the various traditions of Christianity.