hardiness

Noun

• the trait of being willing to undertake things that involve risk or danger
  • the proposal required great boldness
    
  • the plan required great hardiness of heart
    

• the property of being strong and healthy in constitution

Related words

• Synonyms: 
  boldness , daring , hardihood , robustness , lustiness , validity
• Antonyms: 
  timidity , timorousness