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

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

From BBC

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

The simplest way to boil water in a hotel room: immersion heater This little coil is the thing that unlocked my entire travel coffee setup.

From The Verge

When it gets chilly enough to freeze birdbath water, Blackstone recommends an immersion heater, available at Seattle Audubon, as a welcome alternative to chipping out ice.

From Seattle Times

Electric kettles had been experimented with since the 1890s, but the first kettle with a submergible immersion heater inside it was manufactured by the Swan Company in 1922.

From BBC