A furnace is an appliance that heats houses and buildings by burning fuel or circulating hot water. Your furnace might rumble in the basement, sending heat up through your house's radiators.

Most houses in cold climates have a furnace, to warm their rooms during the chilly months of the year. Furnaces also have industrial uses, like burning trash or extracting ore from metal. If someone says, "It's as hot as a furnace in this classroom!" they mean that it's extremely hot. Furnace comes from the Old French fornaise, "oven," with the Latin root word fornacem, "oven or kiln."

Definitions of furnace
  1. noun
    an enclosed chamber in which heat is produced to heat buildings, destroy refuse, smelt or refine ores, etc.
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    a furnace that feeds itself so as to maintain a uniform temperature; used by alchemists
    blast furnace
    a furnace for smelting of iron from iron oxide ores; combustion is intensified by a blast of air
    cremation chamber, crematorium, crematory
    a furnace where a corpse can be burned and reduced to ashes
    a vertical cylindrical furnace for melting iron for casting
    electric furnace
    any furnace in which the heat is provided by an electric current
    a furnace (as on a steam locomotive) in which fuel is burned
    furnace consisting of a special hearth where metal is heated before shaping
    gas furnace
    a furnace that burns gas
    a furnace for incinerating (especially to dispose of refuse)
    a furnace for firing or burning or drying such things as porcelain or bricks
    oil burner, oil furnace
    a furnace that burns oil
    open-hearth furnace
    a furnace for making steel in which the steel is placed on a shallow hearth and flames of burning gas and hot air play over it
    reverberatory furnace
    a furnace in which the material that is being treated is heated indirectly by flames that are directed at the roof and walls of the furnace
    tank furnace
    furnace into one end of which a batch of measured raw materials is shoveled and from the other end molten glass is obtained
    a kiln for making bricks
    dry kiln
    a kiln for drying and seasoning lumber
    gas oven
    a cremation chamber fueled by gas
    a kiln used to reduce naturally occurring forms of calcium carbonate to lime
    a kiln with an inner chamber for firing things at a low temperature
    a kiln for drying hops
    Stassano furnace, electric-arc furnace
    an electric furnace in which an electric arc provides the source of heat for making steel
    type of:
    a natural or artificial enclosed space
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