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.
And one lively female was virtually sleepless, averaging just four minutes of sleep each day. Amber Jorgenson, Discover Magazine, 20 Feb. 2019 Practical and Cute Enter the perfect solution to her sleepless nights. Amanda Garrity, Good Housekeeping, 25 Jan. 2023 Stephen King penned the screenplay for this seminal horror anthology, featuring five freakish stories to give you sleepless nights. Declan Gallagher, EW.com, 19 Jan. 2023 So Good got me through hours of travel, moments with friends, and sleepless nights. Rolling Stone, 27 Dec. 2022 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

Dictionary Entries Near sleepless

Cite this Entry

“Sleepless.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sleepless. Accessed 23 Dec. 2024.

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

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!