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Synonyms

sleeping

American  
[slee-ping] / ˈsli pɪŋ /

noun

  1. the condition of being asleep.

adjective

  1. asleep.

  2. of, relating to, or having accommodations for sleeping.

    a sleeping compartment.

  3. used to sleep in or on.

    a sleeping jacket.

  4. used to induce or aid sleep or while asleep.

    sleeping mask.

Other Word Forms

  • unsleeping adjective

Etymology

Origin of sleeping

Middle English word dating back to 1250–1300; sleep, -ing 1, -ing 2

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The 36-year-old from Northern Ireland shares the first-round lead with American Sam Burns after carding a five-under par 67, ensuring anybody who was sleeping on his chances has been stirred.

From BBC • Apr. 9, 2026

"I wouldn't be sleeping that great," he said.

From BBC • Apr. 7, 2026

Rick Phillips, 53, senior software engineer: One night while I was sleeping, I heard a crash in the room.

From The Wall Street Journal • Apr. 6, 2026

Monteon, who has spent some nights sleeping his car, denied getting physical.

From Los Angeles Times • Apr. 5, 2026

He watched it make its way up the slope towards the Den where the tailless were sleeping.

From "Wolf Brother" by Michelle Paver

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

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.