blue note vs musical note

blue note and musical note both are nouns.

Word	Noun	Adjective	Verb	Adverb
blue note	Yes	No	No	No
musical note	Yes	No	No	No

As nouns, musical note is a hypernym of blue note; that is, musical note is a word with a broader meaning than blue note:

blue note: a flattened third or seventh
musical note: a notation representing the pitch and duration of a musical sound

Other hypernyms of blue note include note, tone.

blue note (noun)	musical note (noun)
a flattened third or seventh	a notation representing the pitch and duration of a musical sound