noun (n)

• the anxious feeling you have when you have the jitters(noun.feeling)

  Synonym:
  jitteriness, jumpiness, restiveness
  

  source: wordnet30
• an uneasy psychological state(noun.state)

  Synonym:
  nerves
  

  source: wordnet30
• a sensitive or highly strung temperament(noun.attribute)

  source: wordnet30
• State or quality of being nervous.(noun)

  source: webster1913