REM sleep

noun

: a state of sleep that recurs cyclically with non-REM sleep several times during a normal period of sleep, is characterized especially by greatly depressed muscle tone, dreaming with vivid imagery, rapid eye movements, and increased neuronal activity in certain brain regions (such as the pons), and typically comprises up to 25% of time spent in sleep
REM sleep, it soon became apparent, occurs in intervals throughout the night, usually four to six times, each lasting from ten minutes to an hour.Martin Gardner
People awakened during REM sleep usually report dreams with visual images and storylike narratives.Lis Harris

called also paradoxical sleep, rapid eye movement sleep

compare slow-wave sleep, non-REM sleep

Examples of REM sleep in a Sentence

Recent Examples on the Web Regularly occurring bouts of retinal movements suggest an REM sleep–like state in jumping spiders Washington State University. Jake Parks, Discover Magazine, 14 Oct. 2024 Fish, however, do not have a neocortex in their brains so the propagating wave sleep is not the same as REM sleep. Discover Magazine, 1 Oct. 2024 Follows newlyweds Hyun-su (the late Parasite start Lee Sun-kyun) and Soo-jin (Jung Yu-mi), whose domestic bliss is disrupted when Hyun-su develops a dangerous REM sleep disorder. Jill Goldsmith, Deadline, 27 Sep. 2024 Treatment options include medications such as clonazepam or stopping a medication that may lead to symptoms of REM sleep behavior disorder.9 No REM: Skipping Sleep Cycle Skipping the REM sleep stage during a sleep cycle is possible, as is getting too little REM sleep per night. Daniel Combs, Verywell Health, 8 Aug. 2024 See all Example Sentences for REM sleep 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'REM sleep.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1963, in the meaning defined above

Time Traveler
The first known use of REM sleep was in 1963

Dictionary Entries Near REM sleep

Cite this Entry

“REM sleep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/REM%20sleep. Accessed 31 Oct. 2024.

Medical Definition

REM sleep

noun
: a state of sleep that recurs cyclically with non-REM sleep several times during a normal period of sleep, is characterized especially by greatly depressed muscle tone, dreaming with vivid imagery, rapid eye movements, and increased neuronal activity in certain brain regions (as the pons), and typically comprises up to 25% of time spent in sleep
REM sleep, it soon became apparent, occurs in intervals throughout the night, usually four to six times, each lasting from ten minutes to an hour.Martin Gardner
People awakened during REM sleep usually report dreams with visual images and storylike narratives.Lis Harris

called also desynchronized sleep, paradoxical sleep, rapid eye movement sleep

compare non-rem sleep
Last Updated: - Updated example sentences
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