dyssomnia
n. any of various sleep disorders marked by abnormalities in the amount, quality, or timing of sleep. In DSM–IV–TR, for example, dyssomnias include primary insomnia, primary hypersomnia, narcolepsy, circadian rhythm sleep disorder, breathing-related sleep disorder, and dyssomnia not otherwise specified, which may be due to excessive noise, light, or other environmental factors; ongoing sleep deprivation; Ekbom’s syndrome; or nocturnal myoclonus.