Fierce/fɪrs/ Definition 1 of 3Pro Tip 1/3Intensity Scale Use 'fierce' for very strong situations, more than just 'strong' or 'heavy'. The debate turned into a fierce argument. Pro Tip 2/3Physical Destruction 'Fierce' often describes things causing damage or destruction. A fierce storm caused widespread flooding. Pro Tip 3/3Emotional Charge Can describe actions filled with strong feelings, like anger. Her fierce defense of her friends was admirable.