noun (n)

• the condition of being concealed or hidden(noun.state)

  Synonym:
  privacy, privateness, secrecy
  

  source: wordnet30
• a covering that serves to conceal or shelter something(noun.artifact)

  Example:
  The simplest concealment is to match perfectly the color of the background.
  

  Synonym:
  cover, covert, screen
  

  source: wordnet30
• the activity of keeping something secret(noun.act)

  Synonym:
  concealing, hiding
  

  source: wordnet30
• The act of concealing; the state of being concealed.(noun)

  source: webster1913