Of or pertaining to a pontiff, or high priest; as, pontifical authority; hence, belonging to the pope; papal.

Of or pertaining to the building of bridges.

proceeding from or ordered by or subject to a pope or the papacy regarded as the successor of the Apostles; "papal dispensation"

denoting or governed by or relating to a bishop or bishops

book containing the text of services which had to be performed by a bishop

Pontiff is used as an alternative form of reference to the Pope. Pontifical has to do with the Pope.

Pontifical, from the Latin pontificalis, is an adjective used to describe anything connected with the office of a prelate, usually a bishop or an abbot. It is often used in connection with the Pope, the Bishop of Rome and bearer of the old Roman title Pontifex Maximus. When used substantively, it can refer to a number of ecclesiastical institutions and practices.