What is the meaning of simplicity?

noun

• The quality of being simple or uncompounded.
  • usage: "the simplicity of a crystal"
  • synonyms: simpleness
• A lack of penetration or subtlety.
  • usage: "they took advantage of her simplicity"
  • synonyms: simpleness, simple mindedness
• Absence of affectation or pretense.
  • synonyms: simmpleness
• Freedom from difficulty or hardship or effort.
  • usage: "he rose through the ranks with apparent ease"; "they put it into containers for ease of transportation"; "the very easiness of the deed held her back"
  • synonyms: ease, easiness, simpleness
• Lack of ornamentation.
  • usage: "the room was simply decorated with great restraint"
  • synonyms: chasteness, restraint, simpleness