furnace
- 01 B2 Upper Intermediate
n.a large machine, usually in a basement, that burns fuel to heat a whole building.
n.an enclosed apparatus used to heat a building by circulating warm air or water through a system of vents or pipes.
Simple“The furnace broke during the coldest week of winter, leaving the house freezing.”
In context“The landlord promised to inspect the gas furnace before the first frost to ensure the heating system was operating at peak efficiency.”
UsageIn British English, 'boiler' is the more common term for a domestic heating unit.
- 02 C1 Advanced
n.a very hot container used for melting metal or making glass.
n.an industrial structure or container designed to produce intense heat for processes such as smelting, refining, or glassmaking.
Simple“Workers wore protective suits while pouring liquid metal from the furnace.”
In context“The blast furnace remained operational twenty-four hours a day to maintain the extreme temperatures required for steel production.”
- 03 B2 Upper Intermediate
n.a place that is uncomfortably hot.
n.a location or environment characterized by oppressive or excessive heat.
Simple“The office becomes a furnace in the afternoon when the sun hits the windows.”
In context“Without a functioning air conditioning system, the top-floor apartment turned into a furnace during the July heatwave.”
- 04 C2 Proficiency
n.a very difficult or painful experience that tests a person.
n.a metaphorical place or period of severe trial, suffering, or intense discipline.
Simple“The soldiers were changed forever by the furnace of the war.”
In context“He emerged from the furnace of political scandal with his reputation damaged but his resolve significantly strengthened.”
- 05 C2 Proficiency
v.to heat something inside a furnace.
v.to subject a material to intense heat within a furnace.
Simple“The raw ore must be furnaced at high temperatures to extract the iron.”
In context“The specialized ceramic components were furnaced for twelve hours to ensure they reached the necessary structural density.”
“In 2024, the new Labour government under Keir Starmer agreed to invest £500m in another Tata business, the Port Talbot steelworks, to build greener electric arc furnaces.”
From Middle English forneys, from Old French fornais (French fournaise), from Latin fornāx.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.