slow-wave sleep

[ sloh-weyv ]
/ ˈsloʊˈweɪv /

noun Physiology.

a recurrent period of deep sleep, typically totaling five or six hours a night, distinguished by the presence of slow brain waves and by very little dreaming.
Compare REM sleep.

Origin of slow-wave sleep

First recorded in 1965–70
Also called S sleep.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019