saint vs St. Mark

saint and St. Mark both are nouns.

Word	Noun	Adjective	Verb	Adverb
saint	Yes	No	Yes	No
St. Mark	Yes	No	No	No

saint (noun)	St. Mark (noun)
person of exceptional holiness	Apostle and companion of Saint Peter; assumed to be the author of the second Gospel
model of excellence or perfection of a kind; one having no equal
a person who has died and has been declared a saint by canonization

saint (verb)	St. Mark (verb)
declare (a dead person) to be a saint
hold sacred