Medical Definition of parasomnia
: any of various disorders of sleep characterized by abnormal behavioral or physiological activity (such as sleepwalking or night terrors) during sleep or in the transitional stage between sleep and wakefulness There is a group of phenomena known as parasomnias, unpleasant physical activities that can occur when someone is in twilight state between deep sleep and wakefulness.—H. Lee Kagan, Discover, December 2008 The REM parasomnias are harder to explain. One, called sleep paralysis, is so terrifying that it has been blamed for reports of demon visitations and alien abductions.—Ann Finkbeiner, New Scientist, 30 Nov. 2013
Seen and Heard
What made you want to look up parasomnia? Please tell us where you read or heard it (including the quote, if possible).