toughness
(noun)
noun
1. enduring strength and energy
Similar word(s): stamina
Definition categories: attribute, endurance
2. the property of being big and strong
Similar word(s): huskiness, ruggedness
Definition categories: attribute, strength
3. the elasticity and hardness of a metal object; its ability to absorb considerable energy before cracking
Similar word(s): temper
Definition categories: attribute, elasticity, snap
4. impressive difficulty
Similar word(s): formidability
Definition categories: attribute, difficultness, difficulty