St. Mark vs Mark the Evangelist

St. Mark and Mark the Evangelist both are nouns.

Word	Noun	Adjective	Verb	Adverb
St. Mark	Yes	No	No	No
Mark the Evangelist	Yes	No	No	No

As nouns, St. Mark and Mark the Evangelist are synonyms defined as:

St. Mark and Mark the Evangelist: Apostle and companion of Saint Peter; assumed to be the author of the second Gospel

Other synonyms of St. Mark include Mark, Saint Mark.

St. Mark (noun)	Mark the Evangelist (noun)
Apostle and companion of Saint Peter; assumed to be the author of the second Gospel	Apostle and companion of Saint Peter; assumed to be the author of the second Gospel