barley water vs broth

barley water and broth both are nouns.

Word	Noun	Adjective	Verb	Adverb
barley water	Yes	No	No	No
broth	Yes	No	No	No

As nouns, broth is a hypernym of barley water; that is, broth is a word with a broader meaning than barley water:

barley water (noun)	broth (noun)
broth used to feed infants	a thin soup of meat or fish or vegetable stock
	liquid in which meat and vegetables are simmered; used as a basis for e.g. soups or sauces