"Sound sleep" refers to a deep, uninterrupted and restful sleep. There are numerous synonyms for this term. One such synonym could be "peaceful sleep," which evokes a sense of calmness and tranquility associated with restful slumber. Another synonym for "sound sleep" is "untroubled sleep," signifying that the mind and body are not hindered by any worries or disruptions during sleep. "Sound slumber," "deep sleep," and "undisturbed sleep" are a few other synonyms for this term. Whatever word choice is used, the ultimate goal is to convey the state of deep relaxation and restoration the body undergoes during a good night's sleep.