noun (n)

• the property of being big and strong(noun.attribute)

  Synonym:
  huskiness, toughness
  

  source: wordnet30
• the quality of being topologically uneven(noun.attribute)

  Example:
  The ruggedness of the mountains.
  

  source: wordnet30
• the quality of being difficult to do(noun.attribute)

  Example:
  The ruggedness of his exams caused half the class to fail.
  

  Synonym:
  hardness
  

  source: wordnet30