woad vs herbaceous plant

woad and herbaceous plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
woad	Yes	No	No	No
herbaceous plant	Yes	No	No	No

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

woad: any of several herbs of the genus Isatis
herbaceous plant: a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests

Other hypernyms of woad include herb.

woad (noun)	herbaceous plant (noun)
any of several herbs of the genus Isatis	a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests
a blue dyestuff obtained from the woad plant