herbal tea vs sage tea

herbal tea and sage tea both are nouns.

Word	Noun	Adjective	Verb	Adverb
herbal tea	Yes	No	No	No
sage tea	Yes	No	No	No

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

Other hyponyms of herbal tea include tisane, dill tea, tea essence.

herbal tea (noun)	sage tea (noun)
tea-like drink made of leaves of various herbs	a beverage prepared by infusion of sage leaves.