noun (n)

• the quality of being valid and rigorous(noun.attribute)

  Synonym:
  cogency, rigor, validity
  

  source: wordnet30
• something hard to endure(noun.attribute)

  Synonym:
  asperity, grimness, hardship, rigor, rigorousness, rigourousness, severeness, severity
  

  source: wordnet30
• excessive sternness(noun.attribute)

  Synonym:
  hardness, harshness, inclemency, rigor, rigorousness, rigourousness, severeness, severity, stiffness
  

  source: wordnet30