chimney vs flue

chimney

noun
  • A vertical tube or hollow column used to emit environmentally polluting gaseous and solid matter (including but not limited to by-products of burning carbon- or hydrocarbon-based fuels); a flue. 

  • A narrow cleft in a rock face; a narrow vertical cave passage. 

  • A black eye; a shiner. 

  • The smokestack of a steam locomotive. 

  • The glass flue surrounding the flame of an oil lamp. 

  • A vagina. 

verb
  • To negotiate a chimney (narrow vertical cave passage) by pushing against the sides with back, feet, hands, etc. 

flue

noun
  • A pipe or duct that carries gaseous combustion products away from the point of combustion (such as a furnace). 

  • In an organ flue pipe, the opening between the lower lip and the languet. 

  • An enclosed passageway in which to direct air or other gaseous current along. 

How often have the words chimney and flue occurred in a corpus of books? (source: Google Ngram Viewer )