Congratulate/kənˈɡrætʃəleɪt/ Definition 1 of 2Pro Tip 1/3Achievement Focus Use 'congratulate' when someone reaches an important milestone or success. Congratulate her on her recent promotion. Pro Tip 2/3Sincerity Matters Express genuine happiness when congratulating, as insincerity can be easily sensed. When you congratulated me on my project, I felt your sincerity. Pro Tip 3/3Not Sarcastic Avoid using 'congratulate' sarcastically since it can offend or confuse others. Congratulate him genuinely, not with a sarcastic tone.