Saint John's vs St. John's

Saint John's and St. John's both are nouns.

Word	Noun	Adjective	Verb	Adverb
Saint John's	Yes	No	No	No
St. John's	Yes	No	No	No

As nouns, Saint John's and St. John's are synonyms defined as:

Saint John's and St. John's: a port and provincial capital of Newfoundland

As nouns, Saint John's and St. John's are synonyms defined as:

Saint John's and St. John's: the capital and largest city of Antigua and Barbuda; located on the island of Antigua

Other synonyms of Saint John's include capital of Antigua and Barbuda.

Saint John's (noun)	St. John's (noun)
a port and provincial capital of Newfoundland	a port and provincial capital of Newfoundland
the capital and largest city of Antigua and Barbuda; located on the island of Antigua	the capital and largest city of Antigua and Barbuda; located on the island of Antigua