residue vs ash

residue and ash both are nouns.

Word	Noun	Adjective	Verb	Adverb
residue	Yes	No	No	No
ash	Yes	No	Yes	No

As nouns, ash is a hyponym of residue; that is, ash is a word with a more specific, narrower meaning than residue:

residue (noun)	ash (noun)
something left after other parts have been taken away	any of various deciduous pinnate-leaved ornamental or timber trees of the genus Fraxinus
matter that remains after something has been removed	strong elastic wood of any of various ash trees; used for furniture and tool handles and sporting goods such as baseball bats
	the residue that remains when something is burned

residue (verb)	ash (verb)
	convert into ashes