noun

toughness

toughness, strength, resilience, difficulty

The toughness of the material was tested.

The toughness of the material was tested.

He showed great toughness during the illness.

He showed great toughness during the illness.

the toughness of ((sth.)) the quality of being strong of ((sth.)) The toughness of the rope was impressive.

Synonyms: strength, durability, resilience, hardness; Antonyms: weakness, softness, fragility

From the adjective 'tough' + the suffix '-ness', which forms nouns indicating a state or quality.

Since 'tough' means strong or difficult, 'toughness' is the quality of being strong or difficult. It's a direct noun conversion.

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