What is Flue?

Flue definition and meaning on Dictionary terms:
a passage or duct for smoke in a chimney.
any duct or passage for air, gas, or the like.
a tube, especially a large one, in a fire-tube boiler.
Music. flue pipe.Also called windway.a narrow slit in the upper end of an organ pipe through which the air current is directed.


reference: www.dictionary.com/browse/flue