rapid eye movement

American  

noun

1. rapidly shifting, continuous movements of the eyes beneath closed lids during the stage of sleep characterized by dreaming.

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rapid eye movement British  

noun

1.  REM.  movement of the eyeballs under closed eyelids during paradoxical sleep, which occurs while the sleeper is dreaming

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Etymology

Origin of rapid eye movement

First recorded in 1915–20

Example Sentences

Researchers found no evidence that slumbering longer at any one stage of sleep affected brain functions, contradicting a long-debated hypothesis that rapid eye movement or REM sleep is more beneficial to healthier brain function.

From Washington Times

They have long thought these insights came from the rapid eye movement stage of sleep, which is rich with dreams and begins an hour or more into the sleep cycle.

From Scientific American

You never enter restful rapid eye movement sleep, since you have spent the night basically holding your breath.

From Washington Post

While in rapid eye movement, or REM, sleep, which is the deepest stage of sleep, the seals stayed upside down, oblivious to their slow descent.

From New York Times

Sleeping for longer, uninterrupted periods of time allows for REM sleep, a period of unconscious rapid eye movement that corresponds with high activity in the brain.

From Washington Post