NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 8,201 terms related to cancer and medicine.
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- sleep disorder
- listen (sleep dis-OR-der)
A disturbance of normal sleep patterns. There are a number of sleep disorders that range from trouble falling asleep, to nightmares, sleepwalking, and sleep apnea (problems with breathing that cause loud snoring). Poor sleep may also be caused by diseases such as heart disease, lung disease, or nerve disorders.