1. The quality of being firm, solid, or stable; lack of softness or looseness
The firmness of the mattress made it comfortable.
A firmeza do colchão o tornou confortável.
2. Steadiness or resoluteness of character; determination and conviction
She spoke with firmness and conviction about her beliefs.
Ela falou com firmeza e convicção sobre suas crenças.
3. Stability or permanence in a relationship or agreement
The firmness of their friendship endured through the years.
A firmeza da amizade deles perdurou ao longo dos anos.