woad vs dye

woad and dye both are nouns.

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

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

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

Other hypernyms of woad include dyestuff.

woad (noun)	dye (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

woad (verb)	dye (verb)
	color with dye
	color for microscopic study