sleepless

adjective sleep·less \ ˈslēp-ləs \

Updated on: 20 Apr 2018

Definition of sleepless

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

See sleepless defined for English-language learners

See sleepless defined for kids

Examples of sleepless in a Sentence

He lay sleepless in bed.

Recent Examples of sleepless from the Web

The first couple of months after the baby arrives are tough and filled with sleepless nights and tending to a baby that needs a lot of attention.

— Time, "Ask Dr. Ruth: Can I Safely Have Sex While Pregnant?," 12 Apr. 2018
This has meant many 17-hour days, sleepless nights, a couple bouts with bronchitis and the flu, and working many weekends and holidays.

— marian kim-phelps, Pomerado News, "A day in the life of a school superintendent," 12 Apr. 2018
That wasn’t the case seven years ago, when McIlroy turned a dream morning into a sleepless night.

— tara sullivan, BostonGlobe.com, "Past failure doesn’t leave Rory McIlroy intimidated," 7 Apr. 2018
These survivors live with anxiety and fear, sleepless nights and wandering thoughts — unable to escape the sights, sounds and smells of Feb. 14: The crunch of glass beneath their feet.

— erika pesantes, Sun-Sentinel.com, "Bodies, blood, bullets: What Parkland survivors saw in ambushed classrooms," 6 Apr. 2018
The consequences of chronic sleep deprivation are far worse than one sleepless night.

— wes judd, Outside Online, "What Happens to Your Body on No Sleep," 2 Apr. 2018
The visiting Honduran players suffered a sleepless night before the game as rotten eggs, dead rats and a host of other distasteful items were thrown through the broken windows of their dilapidated hotel.

— SI.com, "World Cup Countdown: 12 Weeks to Go - How a Match Between Honduras & El Salvador Started a War," 29 Mar. 2018
The product of his sleepless nights is Forbidden, Hall’s most ambitious creative project to date.

— stephen daw, Billboard, "Todrick Hall Tackles the Politics of Race & Sexuality, Talks 'Mentor' Taylor Swift & More," 28 Mar. 2018
Preparer mistakes can lead to an audit, which, as my clients can attest, can cause sleepless nights and an unaffordable IRS bill.

— patrick thomas, Fortune, "Commentary: How to Make Sure Your Tax Preparer Is Worth It," 24 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sleepless.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of sleepless

15th century

in the meaning defined at sense 1

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sleepless Synonyms

SLEEPLESS Defined for English Language Learners

sleepless

adjective

Definition of sleepless for English Language Learners

: without sleep
: not able to sleep

Medical Dictionary

sleepless

adjective sleep·less \ ˈslē-pləs \

medical Definition of sleepless

: not able to sleep : insomniac

—

sleeplessness

noun

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sleepless

Definition of sleepless

sleeplessly

sleeplessness

Examples of sleepless in a Sentence

Recent Examples of sleepless from the Web

First Known Use of sleepless

sleepless Synonyms

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SLEEPLESS Defined for English Language Learners

sleepless

Definition of sleepless for English Language Learners

Medical Dictionary

sleepless

medical Definition of sleepless

sleeplessness

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