St. Peter vs Saint Peter the Apostle

St. Peter and Saint Peter the Apostle both are nouns.

Word	Noun	Adjective	Verb	Adverb
St. Peter	Yes	No	No	No
Saint Peter the Apostle	Yes	No	No	No

As nouns, St. Peter and Saint Peter the Apostle are synonyms defined as:

St. Peter and Saint Peter the Apostle: disciple of Jesus and leader of the Apostles; regarded by Catholics as the vicar of Christ on earth and first Pope

Other synonyms of St. Peter include Peter, Saint Peter, Simon Peter, St. Peter the Apostle.

St. Peter (noun)	Saint Peter the Apostle (noun)
disciple of Jesus and leader of the Apostles; regarded by Catholics as the vicar of Christ on earth and first Pope	disciple of Jesus and leader of the Apostles; regarded by Catholics as the vicar of Christ on earth and first Pope