red dagga vs herb

red dagga and herb both are nouns.

Word	Noun	Adjective	Verb	Adverb
red dagga	Yes	No	No	No
herb	Yes	No	No	No

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

red dagga: relatively nontoxic South African herb smoked like tobacco
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 red dagga include herbaceous plant.

red dagga (noun)	herb (noun)
relatively nontoxic South African herb smoked like tobacco	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