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furnace

American  
[fur-nis] / ˈfɜr nɪs /

noun

  • furnaces
    plural
  1. a structure or apparatus in which heat may be generated, as for heating houses, smelting ores, or producing steam.

  2. a place characterized by intense heat.

    The volcano was a seething furnace.

  3. Astronomy. Furnace, the constellation Fornax.


verb (used with object)

furnaced, furnacing
  1. to heat (a metal piece) in a furnace.

furnace British  
/ ˈfɜːnɪs /

noun

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

  2. a very hot or stifling place

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of furnace

First recorded in 1175–1225; Middle English furneis, furnais, from Old French fornais, fournais, from Latin fornāc- (stem of fornāx “kiln, oven”), akin to formus “warm”

Explanation

A furnace is an appliance that heats houses and buildings by burning fuel or circulating hot water. Your furnace might rumble in the basement, sending heat up through your house's radiators. Most houses in cold climates have a furnace, to warm their rooms during the chilly months of the year. Furnaces also have industrial uses, like burning trash or extracting ore from metal. If someone says, "It's as hot as a furnace in this classroom!" they mean that it's extremely hot. Furnace comes from the Old French fornaise, "oven," with the Latin root word fornacem, "oven or kiln."

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Vocabulary lists containing furnace

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The new furnace would have an annual production capacity of about 1.6 million tons.

From The Wall Street Journal Sep. 16, 2026

The Japanese company is investing about 900 million euros at its Slovakian operating unit to build an electric arc furnace and an air separation unit.

From The Wall Street Journal Sep. 16, 2026

"Every stage is crucial," explains master cymbalsmith Hasan Seker, a burly 56-year-old who co-founded Bosphorus Cymbals in 1996 and is sweating after hauling glowing blanks into and out of the furnace.

From Barron's Aug. 6, 2026

“There was this weird vent, a furnace return, and a tiny cabinet with a door above it,” said Pete Lauenstein.

From Los Angeles Times Jul. 21, 2026

Instead of a furnace like the one our village blacksmith had, this one had a kiln, precariously arranged on four metal plates.

From "The Many Assassinations of Samir, the Seller of Dreams" by Daniel Nayeri

Italy's government says the country's largest steel works must be converted to electric after a court-ordered shutdown of polluting furnaces but, as Rome seeks a buyer, critics say its plan is woefully unsubstantiated.

From Barron's Sep. 17, 2026

But in the meantime, the plant formerly known as Ilva has been ordered to shut off its blast furnaces by October 28 due to the presence of asbestos and illegal levels of fine airborne particles.

From Barron's Sep. 17, 2026

It said the blast furnaces were "no longer financially sustainable," blaming "highly challenging" market conditions, tariffs and costs associated with moving to lower-carbon production techniques.

From BBC Jul. 17, 2026

Chasing demand means ordering specialized vacuum furnaces on two-year-plus lead times, hiring and training people and building up expensive inventories of superalloys, Chiang said.

From The Wall Street Journal Jul. 10, 2026

He gets a job in the gas works in Coventry shoveling coal into the furnaces like Uncle Pa Keating, shoveling coal and waiting for the day he can go to America after me.

From "Angela's Ashes: A Memoir" by Frank McCourt

Every word that he speaks has been fierily furnaced In the blast of a life that has struggled in earnest.

From Home Life of Great Authors by Hattie Tyng Griswold

And the winds blew with excessive heat, as if warmed by the breath of sighs furnaced forth by travellers grieved at being separated from their wives.

From Tales of the Sun or Folklore of Southern India by Mrs. Howard Kingscote

Across a tract of furnaced flints there came a wind of water, From yellow banks with tender hints of Tethys' white-armed daughter.

From The Poems of Henry Kendall With Biographical Note by Bertram Stevens by Henry Kendall

There he lies and sleeps From year to year—in soft Australian nights, And through the furnaced noons, and in the times Of wind and wet!

From The Poems of Henry Kendall With Biographical Note by Bertram Stevens by Henry Kendall

Bake yourselves, kiln-dry yourselves, if you choose, in your furnaced houses at home, but, if you value your health, "reform that altogether" in Italy.

From The Atlantic Monthly, Volume 05, No. 31, May, 1860 by Various

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