parasomnia

This term is a clinical designation used primarily in medical and psychological contexts to categorize a broad spectrum of sleep-related events. It encompasses a variety of distinct phenomena, such as sleepwalking, night terrors, and REM sleep behavior disorder, grouping them under a single diagnostic umbrella based on the occurrence of abnormal activity during sleep transitions.

In a professional setting, the word is used to describe the pathology of the sleep cycle rather than the specific symptoms themselves. While a patient might describe their experience as "nightmares" or "sleepwalking," a clinician uses "parasomnia" to classify the underlying disorder.