violinist vs musician

violinist and musician both are nouns.

Word	Noun	Adjective	Verb	Adverb
violinist	Yes	No	No	No
musician	Yes	No	No	No

As nouns, musician is a hypernym of violinist; that is, musician is a word with a broader meaning than violinist:

Other hypernyms of violinist include instrumentalist, player.

violinist (noun)	musician (noun)
a musician who plays the violin	artist who composes or conducts music as a profession
	someone who plays a music as a profession