furnace

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. An enclosure in which energy in a nonthermal form is converted to heat, especially such an enclosure in which heat is generated by the combustion of a suitable fuel.
2. n. An intensely hot place: the furnace of the sun; an attic room that is a furnace in the summer.
3. n. A severe test or trial: endured the furnace of his friends' blame after the accident.

Century Dictionary and Cyclopedia

1. n. A structure in which to make and maintain a fire the heat of which is to be used for some mechanical purpose, as the melting of ores or metals, the production of steam as a power, the warming of apartments, the baking of pottery, etc.; specifically, a structure of considerable size built of stone or brick, and usually lined with fire-brick, used for some purpose connected with the operation of smelting metals. Furnaces are constructed in a great variety of ways, according to the different purposes to which they are to be applied. See air-furnace, blast-furnace, and hearth.
2. n. Figuratively, a place, time, or occasion of severe torture or great trial.
3. To subject to the action of a furnace; figuratively, to heat as if in a furnace.
4. To throw out, as flames or dull reverberations of sound are emitted by a furnace.
5. To issue forth like flames from a furnace.
6. n. A furnace which is continually rotated or revolved to secure thorough mixture or chemical reaction under heat as respects the charge.

Wiktionary

1. n. A device for heating.
2. n. A device that heats materials being processed in a factory.
3. n. A device that provides heat for a building.
4. n. Any area that is excessively hot.
5. v. To heat in a furnace

GNU Webster's 1913

1. n. An inclosed place in which heat is produced by the combustion of fuel, as for reducing ores or melting metals, for warming a house, for baking pottery, etc.
2. n. A place or time of punishment, affiction, or great trial; severe experience or discipline.
3. n. Obs. or R. To throw out, or exhale, as from a furnace; also, to put into a furnace.

WordNet 3.0

1. n. an enclosed chamber in which heat is produced to heat buildings, destroy refuse, smelt or refine ores, etc.