Having a nightmare is a distressing experience that can leave one feeling anxious and fearful. Luckily, there are several ways to describe this experience using different words. Some synonyms for the phrase "had a nightmare" include had a bad dream, had a disturbing dream, had a frightening dream, had a terrifying dream, and had a horrid dream. Each of these synonyms conveys a slightly different tone or intensity, allowing the speaker to choose the most appropriate word to accurately describe their experience. Whether it's a bad dream that causes a twinge of unease or a terrifying dream that leaves one gasping for breath, there's a word out there to express it.