What is the meaning of firmness?

noun

• The muscle tone of healthy tissue.
  • usage: "his muscular firmness"
  • synonyms: soundness
• The trait of being resolute.
  • usage: "his resoluteness carried him through the battle"; "it was his unshakeable resolution to finish the work"
  • synonyms: resoluteness, firmness of purpose, resolve, resolution
• The property of being unyielding to the touch.
• The quality of being steady or securely and immovably fixed in place.
  • synonyms: steadiness