noun (n)

• an untroubled state; free from disturbances(noun.state)

  Synonym:
  quiet, tranquility
  

  source: wordnet30
• a state of peace and quiet(noun.feeling)

  Synonym:
  quietness, quietude, tranquility
  

  source: wordnet30
• a disposition free from stress or emotion(noun.attribute)

  Synonym:
  placidity, quiet, repose, serenity, tranquility
  

  source: wordnet30
• The quality or state of being tranquil; calmness; composure.(noun)

  source: webster1913