noun (n)

• your overall circumstances or condition in life (including everything that happens to you)(noun.state)

  Example:
  The luck of the Irish.
  

  Synonym:
  circumstances, destiny, fate, fortune, lot, portion
  

  source: wordnet30
• an unknown and unpredictable phenomenon that causes an event to result one way rather than another(noun.phenomenon)

  Example:
  Bad luck caused his downfall.
  

  Synonym:
  chance, fortune, hazard
  

  source: wordnet30
• an unknown and unpredictable phenomenon that leads to a favorable outcome(noun.phenomenon)

  Example:
  It was my good luck to be there.
  They say luck is a lady.
  

  Synonym:
  fortune
  

  source: wordnet30
• That which happens to a person; an event, good or ill, affecting one's interests or happiness, and which is deemed casual; a course or series of such events regarded as occurring by chance; chance; hap; fate; fortune; often, one's habitual or characteristic fortune; as, good, bad, ill, or hard luck. Luck is often used for good luck; as, luck is better than skill.(noun)

  source: webster1913