herba impia vs cotton rose

herba impia and cotton rose both are nouns.

Word	Noun	Adjective	Verb	Adverb
herba impia	Yes	No	No	No
cotton rose	Yes	No	No	No

As nouns, cotton rose is a hypernym of herba impia; that is, cotton rose is a word with a broader meaning than herba impia:

herba impia: (literally an undutiful herb) a variety of cotton rose
cotton rose: any plant of the genus Filago having capitate clusters of small woolly flower heads

Other hypernyms of herba impia include cudweed, filago.

herba impia (noun)	cotton rose (noun)
(literally an undutiful herb) a variety of cotton rose	any plant of the genus Filago having capitate clusters of small woolly flower heads
	Chinese shrub or small tree having white or pink flowers becoming deep red at night; widely cultivated; naturalized in southeastern United States