John Adams vs President John Adams

John Adams and President John Adams both are nouns.

Word	Noun	Adjective	Verb	Adverb
John Adams	Yes	No	No	No
President John Adams	Yes	No	No	No

As nouns, John Adams and President John Adams are synonyms defined as:

John Adams and President John Adams: 2nd President of the United States (1735-1826)

Other synonyms of John Adams include Adams, President Adams.

John Adams (noun)	President John Adams (noun)
2nd President of the United States (1735-1826)	2nd President of the United States (1735-1826)