1. relating to or occurring during sleep or the transition between sleep and wakefulness
Usage: medical/technical term; often used in sleep medicine and neurology

Examples

• Hypnic jerks are involuntary muscle spasms that occur as someone is falling asleep.
• The patient reported hypnic hallucinations upon waking.
• Hypnic headaches typically occur during REM sleep.
• Doctors studied the hypnic phase to better understand sleep disorders.
• Some people experience hypnic starts, sudden awakenings with a sensation of falling.