subdominant vs musical note

subdominant and musical note both are nouns.

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

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

subdominant: (music) the fourth note of the diatonic scale
musical note: a notation representing the pitch and duration of a musical sound

Other hypernyms of subdominant include note, tone.

subdominant (noun)	musical note (noun)
(music) the fourth note of the diatonic scale	a notation representing the pitch and duration of a musical sound