Nastily/ˈnæstɪli/ Definition 1 of 2Pro Tip 1/3Negative Tone Used to express a negative opinion which might be hurtful. She nastily remarked on his outdated style. Pro Tip 2/3Emphasize Rudeness Highlights that the speaker is being intentionally rude or disrespectful. They nastily laughed at the beginner's attempt to dance. Pro Tip 3/3Social Disapproval Its use might lead others to view the speaker negatively. His nastily delivered insult made everyone uncomfortable.