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

For instance, in a steel manufacturing environment, agentic AI could use a digital twin to run continuous micro-experiments on furnace parameters, monitor real-time energy efficiency and automatically adjust settings to reduce energy consumption while preserving quality standards. —Dmitriy Stepanov, Forbes.com, 8 July 2025

It wasn't immediately known how many units were uninhabitable or impacted by the fire, which a caller told officials started in a bedroom closet which contained a furnace unit. —Jim Riccioli, jsonline.com, 1 July 2025

Fire roared to life minutes later, engulfing the store in a furnace of rising panic and confusion. —Jp Mangalindan, Time, 4 June 2025

In another study—currently a preprint awaiting peer review—by the same team, models show that, just over 200 million years after the Big Bang, in the ruins of the very first stars, planets were piecing themselves together around a second generation of stellar furnaces. —Robin George Andrews, Smithsonian Magazine, 30 May 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)