The term 'PERTAINING TO THE PONTIFF' can be summed up by the crossword solution 'PAPAL, ' which is an adjective meaning 'of or relating to the pope, the bishop of Rome and head of the Roman Catholic Church.' The word 'papal' is derived from the Latin word 'PAPA, ' which means 'FATHER.' The pope is the spiritual leader of the Catholic Church and is considered to be the successor of Saint Peter, one of Jesus' original twelve apostles.