Any condition that interferes with sleep other than environmental noises. Can include difficulty sleeping (insomnia), nightmares, night terrors, sleepwalking, and apnea.

a physical condition that interferes with the obtaining of adequate and appropriate sleep and requires medical treatment

A disorder in which a person has difficulty achieving restful, restorative sleep. In addition to other symptoms, people with fibromyalgia usually have a sleep disorder.

A disorder in the sleep patterns. Some sleep disorders can interfere with mental and emotional function, due to their interference with REM sleep.

A constellation of sleep problems and associated features that is detrimental to a person’s health, such as sleep apnea and periodic limb movement disorder. Sleep disorders are diagnosed by specific criteria and are often treatable.

A sleep disorder (somnipathy) is a disorder in the sleep patterns of a person or animal. Some sleep disorders can interfere with mental and emotional function.