hard water

American  

noun

1. water that contains magnesium, calcium, or iron salts and therefore forms a soap lather with difficulty.

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hard water Cultural  

1. Water in which dissolved minerals make it difficult to produce a lather with soap.

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Hard water is usually associated with well water in regions where the rocks contain a large proportion of iron-bearing minerals.

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hard water

Other plastics, including ones promoted as highly recyclable, such as clear polyethylene bottles, which hold some medications, or hard water bottles, are being recycled at just 16%.

From Los Angeles Times ● Jan. 14, 2026

If you recall your high school chemistry class, you know that white vinegar is a weak form of acid and that hard water deposits are alkaline.

From Seattle Times ● Nov. 1, 2022

However, for the sake of both your laundry and washing machine, it's worth buying a hard water test to find out if you have too-high levels of dissolved calcium and magnesium.

From Salon ● Aug. 19, 2022

Some manufacturers recommend running a cleaning cycle periodically with no dishes but with citric acid, vinegar or a dishwasher cleaner to break up mineral deposits and remove films or stains from hard water.

From Washington Post ● Aug. 1, 2022

Stones are hard, water is wet, objects unsupported fall toward the earth’s center.

From "1984" by George Orwell