woad vs dyestuff

woad and dyestuff both are nouns.

Word	Noun	Adjective	Verb	Adverb
woad	Yes	No	No	No
dyestuff	Yes	No	No	No

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

woad: a blue dyestuff obtained from the woad plant
dyestuff: a usually soluble substance for staining or coloring e.g. fabrics or hair

Other hypernyms of woad include dye.

woad (noun)	dyestuff (noun)
any of several herbs of the genus Isatis	a usually soluble substance for staining or coloring e.g. fabrics or hair
a blue dyestuff obtained from the woad plant