national leader vs Nelson Mandela

national leader and Nelson Mandela both are nouns.

Word	Noun	Adjective	Verb	Adverb
national leader	Yes	No	No	No
Nelson Mandela	Yes	No	No	No

national leader (noun)	Nelson Mandela (noun)
a person who is a respected leader in national or international affairs	South African statesman who was released from prison to become the nation's first democratically elected president in 1994 (born in 1918)