hard·​ness | \ ˈhärd-nəs How to pronounce hardness (audio) \

Definition of hardness

1 : the quality or state of being hard
2a : the cohesion of the particles on the surface of a mineral as determined by its capacity to scratch another or be itself scratched — compare mohs' scale
b : resistance of metal to indentation under a static load or to scratching

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Examples of hardness in a Sentence

the hardness of a diamond The wood's hardness makes it suitable for carving.

Recent Examples on the Web

Tempering gives up added hardness in favor of flexibility. Shannon Liao, The Verge, "Why your brand-new smartphone will scratch just as easily as your old one," 19 Oct. 2018 Despite being harder than styrofoam, polystyrene won't be able to hold a candle to the hardness of even your softer steels, and as such would require an absurd amount of maintenance to keep in cutting shape. Eric Limer, Popular Mechanics, "Yes, You Can Make a Knife Out of Styrofoam," 8 Apr. 2019 Unlike soil, stone has a uniform hardness and provides efficient drainage. Peter Martin, Popular Mechanics, "How To Build a Beautiful Bluestone Patio in One Afternoon," 23 Sep. 2016 Calcium hardness from 150 ppm to 250 ppm (parts per million). Danielle Beurteaux, Popular Mechanics, "How to Get Your Swimming Pool Ready for Summer," 18 May 2018 Besides their sought-after clarity, extreme hardness, and entanglement in civil wars, diamonds tell unique geologic stories. Scott K. Johnson, Ars Technica, "Blue diamonds come from ocean floor that is pushed nearly to Earth’s core," 1 Aug. 2018 Graded to an incredibly high 62+ Rockwell hardness, these knives are also fully stain- and rust-resistant, and are precision-balanced and weighted for superior performance. Popular Mechanics, "These Precise Japanese Knives Are a Kitchen Must-Have," 11 Dec. 2018 First, components are designed in thousands of different materials and alloys for reasons of performance (hardness, resistance to corrosion, etc.). WSJ, "While Great, 3-D Printers Have Limitations," 2 Nov. 2018 Adjust the calcium hardness by using calcium chloride. Danielle Beurteaux, Popular Mechanics, "How to Get Your Swimming Pool Ready for Summer," 18 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hardness.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of hardness

before the 12th century, in the meaning defined at sense 1

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Last Updated

20 Jun 2019

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Time Traveler for hardness

The first known use of hardness was before the 12th century

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English Language Learners Definition of hardness

: the quality or state of being hard

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Comments on hardness

What made you want to look up hardness? Please tell us where you read or heard it (including the quote, if possible).


having a desire to acquire more things

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