pandean pipe vs panpipe

pandean pipe and panpipe both are nouns.

Word	Noun	Adjective	Verb	Adverb
pandean pipe	Yes	No	No	No
panpipe	Yes	No	No	No

As nouns, pandean pipe and panpipe are synonyms defined as:

pandean pipe and panpipe: a primitive wind instrument consisting of several parallel pipes bound together

Other synonyms of pandean pipe include syrinx.

pandean pipe (noun)	panpipe (noun)
a primitive wind instrument consisting of several parallel pipes bound together	a primitive wind instrument consisting of several parallel pipes bound together