stonecress vs herb

stonecress and herb both are nouns.

Word	Noun	Adjective	Verb	Adverb
stonecress	Yes	No	No	No
herb	Yes	No	No	No

As nouns, herb is a hypernym of stonecress; that is, herb is a word with a broader meaning than stonecress:

stonecress: any Old World herb of the genus Aethionema; native of sunny limestone habitats
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 stonecress include herbaceous plant.

stonecress (noun)	herb (noun)
any Old World herb of the genus Aethionema; native of sunny limestone habitats	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