What is the meaning of smoothness?

noun

• A texture without roughness; smooth to the touch.
  • usage: "admiring the slim smoothness of her thighs"; "some artists prefer the smoothness of a board"
• Powerful and effective language.
  • usage: "his eloquence attracted a large congregation"; "fluency in spoken and written English is essential"; "his oily smoothness concealed his guilt from the police"
  • synonyms: eloquence, fluency
• The quality of being bland and gracious or ingratiating in manner.
  • synonyms: suavity, suaveness, blandness
• The quality of having a level and even surface.
  • usage: "the water was a glassy smoothness"; "the weather system of the Pacific is determined by the uninterrupted smoothness of the ocean"
• The quality of being free from errors or interruptions.
  • usage: "the five-speed manual gearbox is smoothness personified"