- a menacingly wild, savage, or hostile quality or character: In spite of the fierceness of the enemy barrage, the line was made secure.After many threats, he rushed at me with the fierceness of a wolf.
- violent force, intensity, etc.: Already the sudden storm is passing, and its fierceness is abating.
- furious eagerness or intensity of emotion, etc.: As I read her novel my heart was moved by the fierceness of her love for humanity.
- the quality of being extremely bad or severe: Only by the fifth day, when the fierceness of the headache started to decrease, was she able to move normally again.
