flute player vs instrumentalist

flute player and instrumentalist both are nouns.

Word	Noun	Adjective	Verb	Adverb
flute player	Yes	No	No	No
instrumentalist	Yes	No	No	No

As nouns, instrumentalist is a hypernym of flute player; that is, instrumentalist is a word with a broader meaning than flute player:

Other hypernyms of flute player include musician, player.

flute player (noun)	instrumentalist (noun)
someone who plays the flute	someone who plays a music as a profession