noun (n)

• the property of being strong and healthy in constitution(noun.attribute)

  Synonym:
  lustiness, robustness, validity
  

  source: wordnet30
• the trait of being willing to undertake things that involve risk or danger(noun.attribute)

  Example:
  The plan required great hardiness of heart.
  

  Synonym:
  boldness, daring, hardihood
  Antonym:
  timidity, timorousness
  

  source: wordnet30
• Capability of endurance.(noun)

  source: webster1913