noun (n)

• intense sorrow caused by loss of a loved one (especially by death)(noun.feeling)

  Synonym:
  brokenheartedness, heartache, heartbreak
  

  source: wordnet30
• something that causes great unhappiness(noun.cognition)

  Example:
  Her death was a great grief to John.
  

  Synonym:
  sorrow
  

  source: wordnet30
• Pain of mind on account of something in the past; mental suffering arising from any cause, as misfortune, loss of friends, misconduct of one's self or others, etc.; sorrow; sadness.(noun)

  source: webster1913