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

But now the concern’s more likely to come from masked immigration agents than dangerous forges and furnaces. —Michael Peregrine, Chicago Tribune, 4 May 2026

As for the care and maintenance this home has received, the roof was replaced in 2020, the furnace in 2010, the first floor air conditioning unit was new in 2022, and a new well pump was installed in 2023. —James Alexander, Hartford Courant, 3 May 2026

Get them in the ground about 10 days after your last frost, or when the weather has warmed enough that the furnace doesn’t run much anymore. —Andy Wilcox, Better Homes & Gardens, 1 May 2026

The sleep arrangements at Kelly Ripa and Mark Consuelos’ house involve a body pillow, a Baltic-cold bedroom and a husband who runs hot enough to qualify as a furnace. —Samantha Agate, Fort Worth Star-Telegram, 1 May 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)