furnace

noun

fur·​nace ˈfər-nəs 

: an enclosed structure in which heat is produced (as for heating a house or for reducing ore)

Examples of furnace in a Sentence

Recent Examples on the Web

There’s also evidence that the ship’s engineers left the boilers on, shoveling coal into the furnaces to keep electricity running. —Theresa Braine, New York Daily News, 14 Apr. 2025

The costs of converting to electric furnaces were estimated at £2 billion or more. —Stanley Reed, New York Times, 12 Apr. 2025

Activists would rather see direct reduction furnaces, which are a more environmentally and economically friendly alternative, according to GARD. —Maya Wilkins, Chicago Tribune, 28 Feb. 2025

What causes carbon monoxide? Carbon monoxide is produced any time a fossil fuel is burned, meaning accidental poisoning can occur when home appliances and systems like furnaces, kerosene heaters, stoves, lanterns and generators produce fumes that people breathe in. —Sara Moniuszko, CBS News, 27 Feb. 2025

Word History

Etymology

Middle English fourneyse, fornes, furneis "oven, kiln, furnace," borrowed from Anglo-French furneis, fornays, fornaise (continental Old French forneis —attested once as masculine noun— fornaise, feminine noun), going back to Latin fornāc-, fornāx (also furnāx) "furnace, oven, kiln (for heating baths, smelting metal, firing clay)," from forn-, furn-, base of furnus, fornus "oven for baking" + -āc-, -āx, noun suffix; forn- going back to Indo-European *g^whr̥-no- (whence also Old Irish gorn "piece of burning wood," Old Russian grŭnŭ, gŭrnŭ "cauldron," Russian gorn "furnace, forge," Bosnian-Croatian-Serbian gŕno "coals for heating iron at a smithy," Sanskrit ghṛṇáḥ "heat, ardor"), suffixed derivative of a verbal base *g^wher- "become warm" — more at therm

Note: The variation between -or-, the expected outcome of zero grade, and -ur- in Latin has been explained as reflecting a rural/dialectal change of o to u, borrowing from Umbrian, or the result of a sound change of uncertain conditioning; see most recently Nicholas Zair, "The origins of -urC- for expected -orC- in Latin," Glotta, Band 93 (2017), pp. 255-89.

First Known Use

13th century, in the meaning defined above

Phrases Containing furnace

• blast furnace
• reverberatory furnace

Rhymes for furnace

• externus

Kids Definition

furnace

noun

fur·​nace ˈfər-nəs 

: an enclosed structure in which heat is produced (as for heating a house or melting metals)