toughness has definitions from the field of physics
1
[ noun ] enduring strength and energy

Used in print

(Chicago Daily Tribune...)

Though his character is broader and more comically rounded than the don , he gives it a firmness and toughness - a sort_of peasant dignity - too .

Related terms

endurance legs

2
[ noun ] (physics) the elasticity and hardness of a metal object; its ability to absorb considerable energy before cracking

Synonyms

temper

Related terms

elasticity temper

3
[ noun ] the property of being big and strong

Related terms

strength

4
[ noun ] impressive difficulty

Synonyms

formidability

Related terms

difficulty

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