enthusiast vs friend

enthusiast and friend both are nouns.

Word	Noun	Adjective	Verb	Adverb
enthusiast	Yes	No	No	No
friend	Yes	No	No	No

As nouns, friend is a hypernym of enthusiast; that is, friend is a word with a broader meaning than enthusiast:

Other hypernyms of enthusiast include admirer, booster, champion, protagonist, supporter.

enthusiast (noun)	friend (noun)
an ardent and enthusiastic supporter of some person or activity	a person you know well and regard with affection and trust
a person having a strong liking for something	a person with whom you are acquainted
	an associate who provides cooperation or assistance
	a person who backs a politician or a team etc.