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

Researchers classify them according to three main features: hardness, the way they respond to strain, and the structure formed by ions and proteins.

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

The laser-leading method also struggled to maintain the hardness required for success.

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

There was an edge to his laugh, though, a hardness that I figured was leftover fear.

From "The Rock and the River" by Kekla Magoon

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

From Textbooks ● Jan. 1, 2015

Let us give the name of 'sense-data' to the things that are immediately known in sensation: such things as colours, sounds, smells, hardnesses, roughnesses, and so on.

From The Problems of Philosophy by Russell, Bertrand

She had her full share of difficulties, hardnesses, disappointments, and physical weakness; but, whatever her feelings were, she rose above them, and went on with her work.

From The Angel Adjutant of "Twice Born Men" by Carpenter, Minnie Lindsay Rowell

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

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

The rest, though they are not free from certain hardnesses, have a pathos and greatness in their simplicity, sufficient to endear the legitimate Sonnet to every Reader of just taste.

From Original sonnets on various subjects; and odes paraphrased from Horace by Seward, Anna

Related Words

• firmness