Merry/ˈmeri/ Definition 1 of 2Pro Tip 1/3Festive Greetings Use 'merry' to wish someone a joyous holiday, especially during Christmas. Merry Christmas and a Happy New Year! Pro Tip 2/3Celebratory Tone 'Merry' adds excitement and enthusiasm when discussing celebrations or festivities. We're going to have such a merry celebration for her birthday. Pro Tip 3/3Emotionally Light 'Merry' expresses light-heartedness and is less intense than 'ecstatic' or 'elated'. He always has a merry disposition, even on stressful days.