hardness

American  

[hahrd-nis] / ˈhɑrd nɪs /

noun

1. the state or quality of being hard.

   the hardness of ice.

2. a relative degree or extent of this quality.

   wood of a desirable hardness.

3. that quality in water that is imparted by the presence of dissolved salts, especially calcium sulfate or bicarbonate.

4. unfeelingness or jadedness; callousness.

5. harshness or austerity, as of a difficult existence.

6. South Midland U.S. ill will; bad feelings.

   There's a lot of hardness between those two boys.

7. Mineralogy. the comparative ability of a substance to scratch or be scratched by another.

8. Metallurgy. the measured resistance of a metal to indention, abrasion, deformation, or machining.

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hardness British  

/ ˈhɑːdnɪs /

noun

1. the quality or condition of being hard

2. one of several measures of resistance to indentation, deformation, or abrasion See Mohs scale Brinell hardness number

3. the quality of water that causes it to impair the lathering of soap: caused by the presence of certain calcium salts. Temporary hardness can be removed by boiling whereas permanent hardness cannot

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hardness Scientific  

/ härd′nĭs /

1. A measure of how easily a mineral can be scratched. Hardness is measured on the Mohs scale.

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Etymology

Origin of hardness

First recorded before 900; Middle English hardnes, Old English heardnes; hard, -ness

Example Sentences

Materials with this level of hardness are among the toughest used in industrial applications and rank just below superhard materials such as sapphire and diamond.

From Science Daily • Mar. 13, 2026

USC coach Lincoln Riley said after the Trojans’ victory in the Las Vegas Bowl, “There’s a toughness and a hardness that’s developing within this program.”

From Los Angeles Times • Jan. 4, 2025

"We examined different sand shapes, finding a sand that would give us hardness, combining elements of clay, silt and particle distribution to make sure that we had a high-binding strength soil," says McKay.

From BBC • Nov. 21, 2024

And the novelist Richard Ford once made it clear that questioning Ms. Munro’s mastery over the short story would be akin to doubting the hardness of a diamond or the bouquet of a ripened peach.

From New York Times • May 14, 2024

When I laid my foot on the middle cross bench, its hardness had an invigorating effect on me, as if I had just stepped on solid ground.

From "Life of Pi" by Yann Martel

Related Words

• firmness