sesame vs herb

sesame and herb both are nouns.

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

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

sesame: East Indian annual erect herb; source of sesame seed or benniseed and sesame oil
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 sesame include herbaceous plant.

sesame (noun)	herb (noun)
East Indian annual erect herb; source of sesame seed or benniseed and sesame oil	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