1. the quality or state of being tough; strength, durability, or resilience
Usage: plural form of toughness

Examples

• The different toughnesses of various metals make them suitable for different applications.
• Engineers tested the toughnesses of several plastic compounds.
• The coach admired the mental toughnesses displayed by his players.
• Various toughnesses are required to survive in different climates.
• The material’s multiple toughnesses include resistance to heat and cold.
• Scientists measured the toughnesses of the new composite materials.