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
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Recent Examples of sleepiness
Boost Energy and Alertness Taking a walk in the morning has been associated with lower daytime sleepiness and improved alertness during the day.
—
Heather Jones, Verywell Health, 20 Feb. 2026
At higher doses, kratom reduces anxiety and causes sleepiness, the way strong pain drugs like opioids (heroin or fentanyl) do.
—Gary Kirkilas Ii, Boston Herald, 1 Feb. 2026
The participants were scored on subjective sleepiness (Karolinska Sleepiness Scale), sustained attention (Psychomotor Vigilance Task), working memory (three-back task) and visual search performance.
—New Atlas, 17 Jan. 2026
Your balloon fills up with sleepiness throughout the day.
—Andee Tagle, NPR, 15 Jan. 2026
In a clinical study of tradipitant, side effects were infrequent and mild, with a small percent of users reporting sleepiness and fatigue.
—Emily Kay Votruba, EverydayHealth.com, 8 Jan. 2026
Ounce for ounce, turkey contains less tryptophan—an amino acid popularly blamed for post-Thanksgiving sleepiness—than cheddar cheese or an octopus does.
—The Atlantic Science Desk, The Atlantic, 27 Dec. 2025
Studies showed that some women experienced side effects including dizziness, sleepiness and nausea, and less than 2% had to discontinue Addyi because of them.
—Alice Park, Time, 16 Dec. 2025
Her sleepiness follows her there.
—Literary Hub, 8 Dec. 2025
Heather Jones, Verywell Health, 20 Feb. 2026
At higher doses, kratom reduces anxiety and causes sleepiness, the way strong pain drugs like opioids (heroin or fentanyl) do.
—Gary Kirkilas Ii, Boston Herald, 1 Feb. 2026
The participants were scored on subjective sleepiness (Karolinska Sleepiness Scale), sustained attention (Psychomotor Vigilance Task), working memory (three-back task) and visual search performance.
—New Atlas, 17 Jan. 2026
Your balloon fills up with sleepiness throughout the day.
—Andee Tagle, NPR, 15 Jan. 2026
In a clinical study of tradipitant, side effects were infrequent and mild, with a small percent of users reporting sleepiness and fatigue.
—Emily Kay Votruba, EverydayHealth.com, 8 Jan. 2026
Ounce for ounce, turkey contains less tryptophan—an amino acid popularly blamed for post-Thanksgiving sleepiness—than cheddar cheese or an octopus does.
—The Atlantic Science Desk, The Atlantic, 27 Dec. 2025
Studies showed that some women experienced side effects including dizziness, sleepiness and nausea, and less than 2% had to discontinue Addyi because of them.
—Alice Park, Time, 16 Dec. 2025
Her sleepiness follows her there.
—Literary Hub, 8 Dec. 2025
Recent Examples of Synonyms for sleepiness
Noun
-
However, first-generation antihistamines can also cause drowsiness, sedation, and fatigue, which can affect alertness, concentration, and memory.—
Karen Berger,
Verywell Health,
5 Feb. 2026
-
The virus can lead to severe symptoms, including disorientation, drowsiness, seizures or encephalitis, which is inflammation of the brain.—
Mary Kekatos,
ABC News,
29 Jan. 2026
Noun
-
That mental fatigue is to be expected, Dodgers manager Dave Roberts said, after Yamamoto’s two-year transition from Japan’s professional league to back-to-back World Series titles with the Dodgers.—
Bill Plunkett,
Oc Register,
28 Feb. 2026
-
Prolonged dehydration can lead to a whole host of health issues, like headaches, muscle cramps, and fatigue.—
Amelia McBride,
Travel + Leisure,
27 Feb. 2026
Noun
-
Even winter bedding, electric blankets, and sleeping bags can often be washed at home before storage.—
Nafeesah Allen,
Better Homes & Gardens,
20 Feb. 2026
-
The best dog bed supports a dog's specific sleeping style and needs.—
Kasey Caminiti,
USA Today,
19 Feb. 2026
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
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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
Cite this Entry
“Sleepiness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/sleepiness. Accessed 2 Mar. 2026.
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