flue

noun

ˈflü 

: an enclosed passageway for directing a current: such as

a

: a channel in a chimney for conveying flame and smoke to the outer air

b

: a pipe for conveying flame and hot gases around or through water in a steam boiler

c

: an air channel leading to the lip of a wind instrument

d

: flue pipe

Examples of flue in a Sentence

Recent Examples on the Web

Because ethanol burns cleanly, producing only water vapor and a small amount of carbon dioxide, these fireplaces are ventless and require no chimney or flue. —Angie Hicks, Boston Herald, 30 Nov. 2025

The second is to close the flue in your fireplace. —Derek James, CBS News, 18 Nov. 2025

Near-total capture cheaply To operate the system, flue gas from coal, natural gas, or biomass combustion is cooled and compressed before being fed into an absorption column. —Neetika Walter, Interesting Engineering, 14 Nov. 2025

Close the chimney flue to prevent drafts, moisture, or curious critters from sneaking in. —Jalen Williams, Freep.com, 12 Nov. 2025

Word History

Etymology

origin unknown

First Known Use

1582, in the meaning defined above

Phrases Containing flue

• flue-cured
• flue pipe
• flue stop

Rhymes for flue

• blew
• blue
• boo
• brew
• chew
• chou
• clue
• coo
• coup
• crew
• cue
• dew

Kids Definition

flue

noun

ˈflü 

: an enclosed passageway for directing a current

especially : a channel in a chimney for carrying flame and smoke to the outer air