pontiff vs Holy Father

pontiff and Holy Father both are nouns.

Word	Noun	Adjective	Verb	Adverb
pontiff	Yes	No	No	No
Holy Father	Yes	No	No	No

As nouns, pontiff and Holy Father are synonyms defined as:

Other synonyms of pontiff include Bishop of Rome, Catholic Pope, pope, Roman Catholic Pope, Vicar of Christ.

pontiff (noun)	Holy Father (noun)
the head of the Roman Catholic Church	the head of the Roman Catholic Church