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
  • Taking multiple products with sedating effects can increase drowsiness or cause interactions.
    — Ayesha Gulzar, Verywell Health, 14 Aug. 2026
  • 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
Definition of drowsiness
Noun
  • In melanoma patients, Keytruda treatment can result in fatigue, diarrhea, rash and inflammation of joints and muscles, as well as of healthy organs in some cases.
    — CNN Money, CNN Money, 21 Aug. 2026
  • The product is intended for people navigating screen-heavy workdays, mental fatigue, travel, irregular routines, or periods of rest before returning to focused tasks.
    — William Jones, USA Today, 21 Aug. 2026
Definition of fatigue
Noun
  • Orexin antagonists were developed as a treatment for insomnia, differing from conventional sleeping pills that induce sedation.
    — Harriet Marsden, TheWeek, 20 Aug. 2026
  • The man woke up, managed to escape from his sleeping bag, and then escaped from the bear.
    — Christa Swanson, CBS News, 19 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

Browse Nearby Words

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 25 Aug. 2026.

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