St. Christopher vs Saint Kitts

St. Christopher and Saint Kitts both are nouns.

Word	Noun	Adjective	Verb	Adverb
St. Christopher	Yes	No	No	No
Saint Kitts	Yes	No	No	No

As nouns, St. Christopher and Saint Kitts are synonyms defined as:

St. Christopher and Saint Kitts: the largest of the islands comprising Saint Christopher-Nevis

Other synonyms of St. Christopher include Saint Christopher, St. Kitts.

St. Christopher (noun)	Saint Kitts (noun)
the largest of the islands comprising Saint Christopher-Nevis	the largest of the islands comprising Saint Christopher-Nevis
Christian martyr and patron saint of travellers (3rd century)