paradoxical sleep

American

noun

Physiology.

REM sleep.

paradoxical sleep British

noun

physiol sleep that appears to be deep but that is characterized by a brain wave pattern similar to that of wakefulness, rapid eye movements, and heavier breathing

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of paradoxical sleep

First recorded in 1960–65

Example Sentences

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See Examples For:

paradoxical sleep

REM sleep is often described as "paradoxical sleep" because the body is mostly still while brain activity resembles wakefulness.

From Science Daily ● Sep. 26, 2026

“How can we wake a cat during paradoxical sleep and ask it questions?”

From New York Times ● Oct. 11, 2017

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023