noun (n)

• the quality of being simple or uncompounded(noun.attribute)

  Example:
  The simplicity of a crystal.
  

  Synonym:
  simpleness
  Antonym:
  complexity, complexness
  

  source: wordnet30
• a lack of penetration or subtlety(noun.attribute)

  Example:
  They took advantage of her simplicity.
  

  Synonym:
  simple mindedness, simpleness
  

  source: wordnet30
• absence of affectation or pretense(noun.attribute)

  Synonym:
  simmpleness
  

  source: wordnet30
• freedom from difficulty or hardship or effort(noun.attribute)

  Synonym:
  ease, easiness, simpleness
  Antonym:
  difficultness, difficulty
  

  source: wordnet30
• lack of ornamentation(noun.attribute)

  Synonym:
  chasteness, restraint, simpleness
  

  source: wordnet30
• The quality or state of being simple, unmixed, or uncompounded; as, the simplicity of metals or of earths.(noun)

  source: webster1913