umbelliferous plant vs herb

umbelliferous plant and herb both are nouns.

Word	Noun	Adjective	Verb	Adverb
umbelliferous plant	Yes	No	No	No
herb	Yes	No	No	No

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

umbelliferous plant: any of numerous aromatic herbs of the family Umbelliferae
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 umbelliferous plant include herbaceous plant.

umbelliferous plant (noun)	herb (noun)
any of numerous aromatic herbs of the family Umbelliferae	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