firmness in WordNet English dictionary

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