Merciless/ˈmɜːrsɪləs/ Definition 1 of 1Pro Tip 1/3Emotional Weight Indicates extreme severity or harshness, and carries a strong negative emotion. Her merciless teasing left him feeling humiliated. Pro Tip 2/3Condemning Tone Often implies a judgmental attitude and disapproval towards another's actions. The news article spoke of the merciless nature of the crime. Pro Tip 3/3Intensity Amplifier Used to amplify the intensity or seriousness of a situation, act, or characteristic. The merciless storm destroyed several homes in its path.