noun (n)

• an entertainer who has a sensational effect(noun.person)

  Example:
  She was a blonde bombshell.
  

  source: wordnet30
• a shocking surprise(noun.event)

  Example:
  News of the attack came like a bombshell.
  

  Synonym:
  thunderbolt, thunderclap
  

  source: wordnet30
• an explosive bomb or artillery shell(noun.artifact)

  source: wordnet30
• A bomb. See Bomb, n.(noun)

  source: webster1913