grey hen vs heath hen

grey hen and heath hen both are nouns.

Word	Noun	Adjective	Verb	Adverb
grey hen	Yes	No	No	No
heath hen	Yes	No	No	No

As nouns, grey hen and heath hen are synonyms defined as:

Other synonyms of grey hen include gray hen, grayhen, greyhen.

grey hen (noun)	heath hen (noun)
female black grouse	extinct prairie chicken
	female black grouse