organ stop vs flue stop

organ stop and flue stop both are nouns.

Word	Noun	Adjective	Verb	Adverb
organ stop	Yes	No	No	No
flue stop	Yes	No	No	No

As nouns, flue stop is a hyponym of organ stop; that is, flue stop is a word with a more specific, narrower meaning than organ stop:

Other hyponyms of organ stop include diapason, diapason stop, dulciana, reed stop, sourdine, voix celeste, vox angelica.

organ stop (noun)	flue stop (noun)
a graduated set of organ pipes of like tone quality	an organ stop with the tone of a flue pipe