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 Advertisement Tell your doctor about the pauses, gasping, and any daytime sleepiness. — Angela Haupt, Time, 16 Oct. 2026 Hufanga explained that the drink’s effects can act like alcohol, inducing muscle relaxation, sleepiness, and feelings of well-being. — Sam Jane, Denver Post, 29 Sep. 2026 Other common sleep issues that don’t affect the airways include movement disorders that cause nighttime restlessness or narcolepsy, a neurological disorder that affects the body’s sleep-wake cycles and causes excessive sleepiness. — Samantha Agate, Sacbee.com, 24 Sep. 2026 In young children, THC intoxication can cause profound sleepiness, confusion, impaired coordination, vomiting and changes in heart rate. — Katia Hetter, CNN Money, 10 Sep. 2026 To sleep, no more Two scientists who identified the role that a key neuropeptide plays in the uncontrollable sleepiness of narcolepsy were one of three recipients of the prestigious Lasker Awards, announced Thursday. — O. Rose Broderick, STAT, 10 Sep. 2026 Consuming the oil or leaves can cause vomiting, dizziness, sleepiness, and muscle weakness. — Sarah Bence, Verywell Health, 25 Aug. 2026 Takeda is testing orexin-targeting drugs for sleep apnea and chronic daytime sleepiness. — Harriet Marsden, TheWeek, 20 Aug. 2026 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
Recent Examples of Synonyms for sleepiness
  1. drowsiness
  2. fatigue
  3. sleeping
  4. somnolence
Noun
  • In addition, both magnesium and L-theanine do not cause daytime drowsiness, so they can be taken at any time.
    — Emmanuella Ogbonna, HEALTH, 2 Oct. 2026
  • Provincial traffic police said driver fatigue and drowsiness caused the crash.
    — ABC News, ABC News, 26 Sep. 2026
Definition of drowsiness
Noun
  • Injuries and fatigue hollowed out a once-dominant roster, with Shohei Ohtani’s decision to keep pitching through pain leaving the team without its most potent hitter in October.
    — Los Angeles Times, Los Angeles Times, 16 Oct. 2026
  • Chen advised supervisors facing decision fatigue to review shots within their sequences rather than obsess over individual frames.
    — Davide Abbatescianni, Variety, 15 Oct. 2026
Definition of fatigue
Noun
  • All of the sleeping quarters are situated on the lower level, where two primary bedrooms are accompanied by two guest suites and two additional guest bedrooms.
    — Tori Latham, Robb Report, 14 Oct. 2026
  • Then Digory accidentally unleashes the evil empress Jadis (Emma Mackey, who played Physicist Barbie in Barbie) from a sleeping spell, and chaos breaks out.
    — Jennifer Ouellette, ArsTechnica, 14 Oct. 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 20 Oct. 2026.

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