sleepiness

noun

Definition of sleepinessnext
as in drowsiness
the quality or state of desiring or needing sleep the truck driver keeps a thermos of coffee with him to stave off sleepiness

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of sleepiness Adherence is often low, and untreated sleep apnea can worsen hypertension, atrial fibrillation and the daytime sleepiness. — Jesse M. Pines, Forbes.com, 10 Aug. 2026 Chamomile contains apigenin, an antioxidant that has been shown to promote sleepiness and sleep quality. — Mura Dominko, Martha Stewart, 9 Aug. 2026 Throughout the studies, participants also reported less daytime sleepiness, less frequent muscle weakness, and greater attentiveness. — Elaine Chen, STAT, 5 Aug. 2026 Loud snoring, daytime sleepiness and obesity are common signs. — Hanna Wickes, Kansas City Star, 4 Aug. 2026 The benefits of an early nap can wear off too early in the day, leading to afternoon sleepiness. — Heidi Moawad, Verywell Health, 21 July 2026 Melatonin the hormone released at night that triggers sleepiness also declines with age, and perimenopause brings a significant drop that makes sound sleep harder to come by. — Hanna Wickes, Fort Worth Star-Telegram, 17 July 2026 Gamma-wave strength rose across brain regions during therapy, and sleepiness was the most common side effect. — Samantha Agate, Sacbee.com, 13 July 2026 In the study, people who reported excessive daytime sleepiness had higher odds of hypertension than those who didn’t. — Zoe Cunniffe, Health, 18 June 2026
Recent Examples of Synonyms for sleepiness
  1. drowsiness
  2. fatigue
  3. sleeping
  4. somnolence
Noun
  • These older medications were also likely to increase cognitive impairment, such as drowsiness, confusion, slowed thinking, or diminished school or work performance, according to the study authors.
    — Rob Williams, EverydayHealth.com, 30 July 2026
  • Some symptoms of diphenhydramine poisoning include drowsiness, agitation, fast heart rate, nausea, vomiting, hallucinations, seizures, dangerous heart rhythm and loss of consciousness.
    — Angelica Stabile, FOXNews.com, 19 June 2026
Definition of drowsiness
Noun
  • Rangers starter Jacob deGrom, who has been battling a left hip and glute injury since the All-Star break, was pulled after two innings because of right triceps fatigue.
    — ABC News, ABC News, 14 Aug. 2026
  • Investigators also found signs of metal fatigue at the base of the fan blade that broke off, despite recent inspections of the fan blades.
    — Kris Van Cleave, CBS News, 14 Aug. 2026
Definition of fatigue
Noun
  • Wellhouse Leisure The little top hat-like pop-up roof is of no use in expanding sleeping capacity, as it's installed exclusively for raising the snug interior to a standing height over 6 feet.
    — New Atlas, New Atlas, 13 Aug. 2026
  • Most camper vans have a small bed in the back, usually a convertible sofa or platform bed, and some have pop-tops for extra sleeping space for kids.
    — Sara Hansen, Denver Post, 11 Aug. 2026
Definition of sleeping
Noun
  • From there, the story builds on the uncertainty, rocking the somnolence of a small town in the province of Badajoz, and forcing a community to choose between disbelief and the need to prove what can’t be seen.
    — Emiliano De Pablos, Variety, 9 Feb. 2026
  • The people went to the emergency department with tachycardia, confusion, anxiety or somnolence, and nausea after eating gummy candies labeled as containing Amanita muscaria mushrooms.
    — Beth Mole, Ars Technica, 19 July 2024
Definition of somnolence

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sleep in
sleepiness
sleeping
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Cite this Entry

“Sleepiness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/sleepiness. Accessed 18 Aug. 2026.

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More from Merriam-Webster on sleepiness

Nglish: Translation of sleepiness for Spanish Speakers

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