noun (n)

• characterized by a lack of openness (especially about one's actions or purposes)(noun.attribute)

  Synonym:
  closeness
  Antonym:
  nakedness, openness
  

  source: wordnet30
• the trait of keeping things secret(noun.attribute)

  Synonym:
  secrecy, silence
  

  source: wordnet30
• The quality of being secretive; disposition or tendency to conceal.(noun)

  source: webster1913