flue vs chimney

flue and chimney both are nouns.

Word	Noun	Adjective	Verb	Adverb
flue	Yes	No	No	No
chimney	Yes	No	No	No

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

flue: a conduit to carry off smoke
chimney: a vertical flue that provides a path through which smoke from a fire is carried away through the wall or roof of a building

Other hyponyms of flue include chimneystack, lamp chimney.

flue (noun)	chimney (noun)
a conduit to carry off smoke	a vertical flue that provides a path through which smoke from a fire is carried away through the wall or roof of a building
organ pipe whose tone is produced by air passing across the sharp edge of a fissure or lip	a glass flue surrounding the wick of an oil lamp
flat bladelike projection on the arm of an anchor