water softener

American  

noun

1. any of a group of substances that when added to water containing calcium and magnesium ions cause the ions to precipitate or change their usual properties: used in the purification of water for the laboratory, and for giving water more efficient sudsing ability with soap.

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water softener British  

noun

1. any substance that lessens the hardness of water, usually by precipitating or absorbing calcium and magnesium ions

2. a tank, apparatus, or chemical plant that is used to filter or treat water to remove chemicals that cause hardness

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Example Sentences

I reached out to the company that installed our water softener and purification system.

From Seattle Times

A combination water softener/carbon system or salt-free water conditioner/carbon system is typically recommended for homes supplied by city water.

From Washington Post

"Homeowners can — and should — take preventative measures by using a water softener to preserve their belongings."

From Salon

This is done by adding phosphate to keep the minerals suspended in the water or by installing an ion exchange water softener.

From Washington Post

It is used in the manufacture of glass, in some detergents and as a water softener.

From New York Times