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hardness JUST WRITTEN FOR YOU

/ˈhɑrdnəs/ · hard·ness
noun
  1. The quality of being hard. The hardness of the diamond made it difficult to cut.
  2. An instance of this quality; hardship. The hardness of the winter made it difficult for the crops to grow.
  3. The quantity of calcium carbonate dissolved in water, usually expressed in parts per million (ppm). The hardness of the water was measured at 200 ppm.
Did you know? The concept of hardness has been a crucial factor in the development of various technologies, including cutting tools and water treatment systems.
Written by Lexi Wordsworth, Dictionary Editor 0 lookups Added Jul 15, 2026