pyrola vs herb

pyrola and herb both are nouns.

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

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

pyrola: any of several evergreen perennials of the genus Pyrola
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 pyrola include herbaceous plant.

pyrola (noun)	herb (noun)
any of several evergreen perennials of the genus Pyrola	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