boiler

American  

[boi-ler] / ˈbɔɪ lər /

noun

1. a closed vessel or arrangement of vessels and tubes, together with a furnace or other heat source, in which steam or other vapor is generated from water to drive turbines or engines, supply heat, process certain materials, etc.

2. a vessel, as a kettle, for boiling or heating.

3. British. a large tub in which laundry is boiled or sterilized.

4. a tank in which water is heated and stored, as for supplying hot water.

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boiler British  

/ ˈbɔɪlə /

noun

1. a closed vessel or arrangement of enclosed tubes in which water is heated to supply steam to drive an engine or turbine or provide heat

2. a domestic device burning solid fuel, gas, or oil, to provide hot water, esp for central heating

3. a large tub for boiling laundry

4. a tough old chicken for cooking by boiling

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Other Word Forms

• boilerless adjective

Etymology

Origin of boiler

First recorded in 1530–40; boil ¹ + -er ¹

Example Sentences

The indoor unit is about the size of a gas boiler, while the size of the cylinder depends on the property.

From BBC • Mar. 24, 2026

On the Chesapeake Bay, market hunters favored punt guns—cannons weighing up to 200 pounds, with barrels made from boiler pipe—that could bring down 100 ducks with one shot.

From The Wall Street Journal • Mar. 23, 2026

Whereas a gas boiler might heat water to 70C to run round your radiators, heat pumps work better at 45C.

From BBC • Mar. 22, 2026

Krauze joined what was then called the Vladimir Lenin shipyard in 1983, first in a coal-fired boiler room and later operating a crane.

From Barron's • Mar. 7, 2026

Sometimes Francie came across a bonanza: the bottom of a discarded wash boiler.

From "A Tree Grows in Brooklyn" by Betty Smith

Related Words

• heater
• heating system
• incinerator
• kiln
• stove