sleeping pill; sleep medication
(one's) sleeping hours; hours of sleep
lack of sleep; sleep deprivation
hypnopaedia; hypnopedia; sleep-learning
sleep apnea syndrome; SAS
sleepwalking; somnambulism
sleep debt; sleep deficit
sleeping sickness; sleeping disease
short sleeper; person who does not need much sleep
inactive bank account (no withdrawals or deposits made, and to which the owner's rights have been terminated)
circadian rhythm sleep-wake disorder; CRSWD
National Sleep Foundation
Japanese Society of Sleep Research; JSSR