sleepless

adjective

sleep·​less ˈslēp-ləs How to pronounce sleepless (audio)
1
: not able to sleep
lay sleepless with fever
2
: affording no sleep
sleepless nights
3
: unceasingly active or operative
sleepless casinos
sleeplessly adverb
sleeplessness noun

Examples of sleepless in a Sentence

He lay sleepless in bed.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Jaonaay spent three to four months with producer Karn of Yented crafting the modern R&B track, which captures the sleepless nights and racing thoughts of new love. Naman Ramachandran, Variety, 12 Sep. 2025 Edelman is helping fans get rid of sleepless nights by not only encouraging them to take the sleep-aid, but also by giving his weekly picks to help people make smarter lineup decisions. Dj Siddiqi, Forbes.com, 11 Sep. 2025 What happened next has caused Cadrez multiple sleepless nights. Troy Renck, Denver Post, 1 Sep. 2025 His sleepless stare has amused viewers, many of whom said the dog's face perfectly captured the feeling of trying to enjoy a holiday under less-than-ideal conditions. Melissa Fleur Afshar, MSNBC Newsweek, 25 Aug. 2025 See All Example Sentences for sleepless

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of sleepless was in the 15th century

Cite this Entry

“Sleepless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sleepless. Accessed 16 Sep. 2025.

Kids Definition

sleepless

adjective
sleep·​less ˈslē-pləs How to pronounce sleepless (audio)
1
: not able to sleep
2
: marked by the absence of sleep
a sleepless night
3
: unceasingly alert or active
sleeplessly adverb
sleeplessness noun

Medical Definition

sleepless

adjective
sleep·​less ˈslē-pləs How to pronounce sleepless (audio)
: not able to sleep : insomniac
sleeplessness noun

More from Merriam-Webster on sleepless

Last Updated: - Updated example sentences
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