residue vs dottle

residue and dottle both are nouns.

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

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

residue: matter that remains after something has been removed
dottle: the residue of partially burnt tobacco left caked in the bowl of a pipe after smoking

Other hyponyms of residue include crackling, greaves, ash, cotton cake, cottonseed cake, brewer's grain, draff, spent grain.

residue (noun)	dottle (noun)
something left after other parts have been taken away	the residue of partially burnt tobacco left caked in the bowl of a pipe after smoking
matter that remains after something has been removed