noun (n)

• an unrestrained expression of emotion(noun.communication)

  Synonym:
  blowup, ebullition, effusion, gush
  

  source: wordnet30
• a sudden intense happening(noun.event)

  Example:
  An outburst of heavy rain.
  

  Synonym:
  burst, flare-up
  

  source: wordnet30
• a sudden violent disturbance(noun.act)

  Synonym:
  tumultuous disturbance
  

  source: wordnet30
• A bursting forth.(noun)

  source: webster1913