hardness

American  

[hahrd-nis] / ˈhɑrd nɪs /

noun

• hardnesses
  plural

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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Other Word Forms

Noun Inflected Forms

• hardnesses
  plural

Etymology

Origin of hardness

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

Example Sentences

See Examples For:

hardness hardnesses

Lorenz is the mission’s architect, responsible for figuring out the atmosphere’s turbulence, the hardness of the rocks for a sampling drill, and how much light will be available to allow Dragonfly’s sensors to navigate.

From Los Angeles Times ● Aug. 22, 2026

With those adjustments, the team successfully produced cemented carbide through AM without sacrificing its hardness.

From Science Daily ● Aug. 4, 2026

The team first measured jaw hardness using nanoindentation, a technique that presses into a material at a microscopic scale.

From Science Daily ● Jul. 16, 2026

It is a pas de deux of contrasts—roughness and polish, hardness and softness, danger and safety.

From The Wall Street Journal ● May 22, 2026

Her face was a round and freckled apple, but there was hardness in her eyes.

From "The Underground Railroad: A Novel" by Colson Whitehead

Mineral lattices have important implications for mineral properties, as exemplified by the relative hardnesses of diamond and graphite.

From Textbooks ● Jan. 1, 2015

The hardnesses of line, gesture, and feature in the German example, though two centuries at least later, are, I think, equally notable.

From Modern Painters, Volume IV (of V) by John Ruskin

Nevertheless the excitement of it had thrilled and broken up the hardnesses of her own nature.

From Sir George Tressady — Volume II by Mrs. Humphry Ward

She had small hardnesses and little vulgarities of manner that drove him mad.

From Casa Braccio, Volumes 1 and 2 by J. André Castaigne

No doubt, then, the hardnesses and difficulties of any one's lot are part of the divine ordering for the best growth of the person's life.

From Making the Most of Life by J. R. (James Russell) Miller

Related Words

• firmness