herb tea vs dill tea

herb tea and dill tea both are nouns.

Word	Noun	Adjective	Verb	Adverb
herb tea	Yes	No	No	No
dill tea	Yes	No	No	No

As nouns, dill tea is a hyponym of herb tea; that is, dill tea is a word with a more specific, narrower meaning than herb tea:

Other hyponyms of herb tea include tisane, sage tea, tea essence.

herb tea (noun)	dill tea (noun)
tea-like drink made of leaves of various herbs	a beverage of a dill infusion