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 Your circadian rhythm is an internal 24-hour clock that helps regulate alertness and sleepiness. — Emily Cegielski, Flow Space, 28 Oct. 2026 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
Recent Examples of Synonyms for sleepiness
  1. drowsiness
  2. fatigue
  3. sleeping
  4. somnolence
Noun
  • Surveys have repeatedly shown that Americans don't like the current clock changes, with lawmakers and physicians blaming the regular time shifts for drowsiness, inconveniences and even risks to health.
    — Arkansas Online, Arkansas Online, 2 Nov. 2026
  • The Cleveland Clinic notes that as bedtime approaches, the body begins lowering its core temperature as part of the circadian rhythm that signals drowsiness.
    — Hanna Wickes, Fort Worth Star-Telegram, 22 Oct. 2026
Definition of drowsiness
Noun
  • The Latvian is reportedly dealing with recurring symptoms tied to Postural Orthostatic Tachycardia Syndrome (POTS), which can cause dizziness and fatigue.
    — Ryan Morik OutKick, FOXNews.com, 6 Nov. 2026
  • In studies, withdrawal from kratom has appeared mild on a scale that measures clinical opioid withdrawal, with symptoms like anxiety, fatigue, gastrointestinal issues, and restlessness.
    — Theresa Gaffney, STAT, 6 Nov. 2026
Definition of fatigue
Noun
  • Families would do well to check into either the Suisho suite—spacious and comfortable in accommodating rollaway beds or cots, with private dining available on the balcony—or Kinu, with its tatami mat floor sleeping area with family-friendly futons.
    — Condé Nast, Condé Nast Traveler, 5 Nov. 2026
  • Evidence remains mixed, and dreams could also be an experiential by-product of useful sleeping-brain activity, rather than an adaptation with its own job description.
    — New Atlas, New Atlas, 2 Nov. 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 11 Nov. 2026.

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