mouse-ear chickweed vs herb

mouse-ear chickweed and herb both are nouns.

Word	Noun	Adjective	Verb	Adverb
mouse-ear chickweed	Yes	No	No	No
herb	Yes	No	No	No

As nouns, herb is a hypernym of mouse-ear chickweed; that is, herb is a word with a broader meaning than mouse-ear chickweed:

mouse-ear chickweed: any of various plants related to the common chickweed
herb: a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests

Other hypernyms of mouse-ear chickweed include herbaceous plant.

mouse-ear chickweed (noun)	herb (noun)
any of various plants related to the common chickweed	aromatic potherb used in cookery for its savory qualities
	a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests