organ stop vs organ pipe

organ stop and organ pipe both are nouns.

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

As nouns, organ pipe is a hypernym of organ stop; that is, organ pipe is a word with a broader meaning than organ stop:

Other hypernyms of organ stop include pipe, pipework.

organ stop (noun)	organ pipe (noun)
a graduated set of organ pipes of like tone quality	the flues and stops on a pipe organ