Saint Andrew vs Andrew

Saint Andrew and Andrew both are nouns.

Word	Noun	Adjective	Verb	Adverb
Saint Andrew	Yes	No	No	No
Andrew	Yes	No	No	No

As nouns, Saint Andrew and Andrew are synonyms defined as:

Saint Andrew and Andrew: (New Testament) disciple of Jesus; brother of Peter; patron saint of Scotland

Other synonyms of Saint Andrew include Saint Andrew the Apostle, St. Andrew.

Saint Andrew (noun)	Andrew (noun)
(New Testament) disciple of Jesus; brother of Peter; patron saint of Scotland	(New Testament) disciple of Jesus; brother of Peter; patron saint of Scotland