noun (n)

• the feeling that accompanies an experience of being thwarted in attaining your goals(noun.feeling)

  Synonym:
  defeat
  

  source: wordnet30
• an act of hindering someone's plans or efforts(noun.act)

  Synonym:
  foiling, thwarting
  

  source: wordnet30
• a feeling of annoyance at being hindered or criticized(noun.feeling)

  Example:
  Her constant complaints were the main source of his frustration.
  

  source: wordnet30
• The act of frustrating; disappointment; defeat; as, the frustration of one's designs(noun)

  source: webster1913