immersion heater

American  

noun

1. a small electric coil used to heat a liquid, as a cup of water, in which it is immersed.

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immersion heater British  

noun

1. an electrical device, usually thermostatically controlled, for heating the liquid in which it is immersed, esp as a fixture in a domestic hot-water tank

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Etymology

Origin of immersion heater

First recorded in 1910–15

Example Sentences

Now the family use a small immersion heater for hot water, which usually is enough for a couple of showers.

From BBC • Apr. 22, 2026

However, you also need to factor in the costs of removing the existing central heating system and investing in an electric immersion heater for hot water.

From BBC • Feb. 4, 2023

In homes that use exclusively electric wallpaper, this can be provided by an electric immersion heater.

From BBC • Feb. 4, 2023

The man, aged in his thirties, had been rationing his electricity by using his kettle to bathe - turning on the immersion heater for a shower just once a fortnight.

From BBC • Mar. 6, 2022

One night, when Arthur was expressing bafflement at what was wrong with the immersion heater I asked him how long he'd been a plumber.

From The Guardian • Feb. 4, 2011