noun (n)

• unskillfulness resulting from a lack of training(noun.cognition)

  Synonym:
  awkwardness, clumsiness, ineptness, maladroitness, slowness
  

  source: wordnet30
• having no qualities that would render it valuable or useful(noun.attribute)

  Synonym:
  worthlessness
  Antonym:
  worth
  

  source: wordnet30
• The quality of being inept; unfitness; inaptitude; unsuitableness.(noun)

  source: webster1913