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

Using a 10-liter reactor, heat and pressure were applied to turn soggy stillage into a fine black powder, which was then refined in a furnace into two distinct materials. —Mrigakshi Dixit, Interesting Engineering, 25 Mar. 2026

Workers of German steel manufacturer Salzgitter AG stand in front of a furnace at a plant in Salzgitter, Germany, March 1, 2018. —Holly Ellyatt, CNBC, 24 Mar. 2026

Think of pulling on a wad of gum in your mouth – that thin strand is like the fiber, except scientists slowly lower the big preform into the furnace and pull out the small fiber quickly. —John Ballato, The Conversation, 24 Mar. 2026

As is the band’s custom, the lyrics might evoke despair, but the furnace of hooks and harmonies suggests total emotional overload is its own kind of salvation. —Nina Corcoran, Pitchfork, 23 Mar. 2026

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)