An oil furnace for heating a building


From Middle English forneys, from Old French fornais (French fournaise), from Latin fornāx.



furnace (plural furnaces)

  1. (UK) An industrial heating device, e.g. for smelting metal or baking ceramics.
  2. (US, Canada) A device that provides heat for a building; a space heater.
  3. (informal) Any area that is excessively hot.
  4. (figuratively) A place or time of punishment, affliction, or great trial; severe experience or discipline.
    • c. 1530, William Tyndale, Tyndale Bible, Deuteronomy 4:20:
      For the Lorde toke you and broughte you out of the yernen fornace of Egipte, to be vnto him a people of enheritaunce, as it is come to passe this daye.
    • 1866, Herman Melville, Battle-Pieces and Aspects of the War[1], Supplement:
      For that heroic band—those children of the furnace who, in regions like Texas and Tennessee, maintained their fidelity through terrible trials—we of the North felt for them, and profoundly we honor them.

Derived termsEdit



furnace (third-person singular simple present furnaces, present participle furnacing, simple past and past participle furnaced)

  1. To heat in a furnace.
  2. To exhale like a furnace.