President John F. Kennedy vs Jack Kennedy

President John F. Kennedy and Jack Kennedy both are nouns.

Word	Noun	Adjective	Verb	Adverb
President John F. Kennedy	Yes	No	No	No
Jack Kennedy	Yes	No	No	No

As nouns, President John F. Kennedy and Jack Kennedy are synonyms defined as:

President John F. Kennedy and Jack Kennedy: 35th President of the United States; established the Peace Corps; assassinated in Dallas (1917-1963)

Other synonyms of President John F. Kennedy include JFK, John Fitzgerald Kennedy, Kennedy, President Kennedy.

President John F. Kennedy (noun)	Jack Kennedy (noun)
35th President of the United States; established the Peace Corps; assassinated in Dallas (1917-1963)	35th President of the United States; established the Peace Corps; assassinated in Dallas (1917-1963)