cochin china vs domestic fowl

cochin china and domestic fowl both are nouns.

Word	Noun	Adjective	Verb	Adverb
cochin china	Yes	No	No	No
domestic fowl	Yes	No	No	No

As nouns, domestic fowl is a hypernym of cochin china; that is, domestic fowl is a word with a broader meaning than cochin china:

cochin china: Asian breed of large fowl with dense plumage and feathered legs
domestic fowl: a domesticated gallinaceous bird thought to be descended from the red jungle fowl

Other hypernyms of cochin china include fowl, poultry.

cochin china (noun)	domestic fowl (noun)
Asian breed of large fowl with dense plumage and feathered legs	a domesticated gallinaceous bird thought to be descended from the red jungle fowl