toughness

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toughness

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From Middle English toughnesse, towghnesse, towghenesse, equivalent to tough +‎ -ness.

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toughness (countable and uncountable, plural toughnesses)

1. (uncountable) The state of being tough.
   1. (materials science, physics, of a metal) Resistance to fracture when stressed, or the degree of such resistance.
   2. (psychologically, emotionally, or biologically) Fortitude; hardiness; mettle.

      Hyponym: intestinal fortitude

2. A formidable difficulty.

• graph toughness

• oughtness