furnace

C1 · Advanced Countable noun Science Technical

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.

“Workers wore protective suits while pouring liquid metal from the furnace.”

“The blast furnace remained operational twenty-four hours a day to maintain the extreme temperatures required for steel production.”

B2 · Upper Intermediate Countable noun Informal

n. a place that is uncomfortably hot.

n. a location or environment characterized by oppressive or excessive heat.

“The office becomes a furnace in the afternoon when the sun hits the windows.”

“Without a functioning air conditioning system, the top-floor apartment turned into a furnace during the July heatwave.”

C2 · Proficiency Countable noun Literary

n. a very difficult or painful experience that tests a person.

n. a metaphorical place or period of severe trial, suffering, or intense discipline.

“The soldiers were changed forever by the furnace of the war.”

“He emerged from the furnace of political scandal with his reputation damaged but his resolve significantly strengthened.”

C2 · Proficiency Science Technical

v. to heat something inside a furnace.

v. to subject a material to intense heat within a furnace.

“The raw ore must be furnaced at high temperatures to extract the iron.”

“The specialized ceramic components were furnaced for twelve hours to ensure they reached the necessary structural density.”