noun (n)

• the state of being emotionally aroused and worked up(noun.state)

  Synonym:
  excitement, fervor, fervour, inflammation
  

  source: wordnet30
• the neural or electrical arousal of an organ or muscle or gland(noun.state)

  Synonym:
  innervation, irritation
  

  source: wordnet30
• something that agitates and arouses(noun.act)

  Synonym:
  excitement
  

  source: wordnet30
• The act of exciting or putting in motion; the act of rousing up or awakening.(noun)

  source: webster1913