noun (n)

• the condition of being unable to perform as a consequence of physical or mental unfitness(noun.state)

  Example:
  Reading disability.
  

  Synonym:
  disablement, handicap, impairment
  

  source: wordnet30
• State of being disabled; deprivation or want of ability; absence of competent physical, intellectual, or moral power, means, fitness, and the like.(noun)

  source: webster1913