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
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Recent Examples of sleepiness
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
This can lead to feeling ill, with symptoms such as sleepiness, physical fatigue, headache, and more.
—Ashley Olivine, Verywell Health, 5 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
For infants, additional red flags include difficulty feeding, fewer wet diapers, fast or labored breathing or unusual sleepiness.
—Katia Hetter, CNN Money, 4 Dec. 2025
The post-feast nap is often blamed on turkey, which contains tryptophan — an amino acid linked to sleepiness.
—Khloe Quill, FOXNews.com, 27 Nov. 2025
Emily Kay Votruba, EverydayHealth.com, 8 Jan. 2026
This can lead to feeling ill, with symptoms such as sleepiness, physical fatigue, headache, and more.
—Ashley Olivine, Verywell Health, 5 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
For infants, additional red flags include difficulty feeding, fewer wet diapers, fast or labored breathing or unusual sleepiness.
—Katia Hetter, CNN Money, 4 Dec. 2025
The post-feast nap is often blamed on turkey, which contains tryptophan — an amino acid linked to sleepiness.
—Khloe Quill, FOXNews.com, 27 Nov. 2025
Recent Examples of Synonyms for sleepiness
Noun
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In addition, overdose carries serious and potentially life-threatening risks including confusion, seizures, drowsiness, dry mouth, and shortness of breath, which can be exacerbated by alcohol use.—
David J. Neal,
Miami Herald,
12 Jan. 2026
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Taking magnesium and sleep aids together can intensify drowsiness, leaving you dizzy or fatigued the next day.—
Abby Norman,
Verywell Health,
12 Jan. 2026
Noun
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All of that adds up to headaches, fatigue and body aches that last longer.—
Deirdre Bardolf,
FOXNews.com,
12 Jan. 2026
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Indeed, exercise in general improves fatigue, energy, and vitality, according to research, so getting in some movement first thing in the morning can do all that.—
Danielle Zickl,
Outside,
11 Jan. 2026
Noun
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They’re combined with a non-toxic, hypoallergenic down alternative filling, creating a plush and luxurious sleeping experience that’s designed for back, side, and stomach sleepers.—
Megan Schaltegger,
PEOPLE,
7 Jan. 2026
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People with strong circadian rhythms are usually able to stick to regular times for sleeping and activity, even with schedule or season changes, experts say.—
Khloe Quill,
FOXNews.com,
6 Jan. 2026
Noun
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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
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Organized labor shows corporate managements who’s the boss: This year continued the strengthening of union power after decades of somnolence.—
Michael Hiltzik,
Los Angeles Times,
21 Dec. 2023
Cite this Entry
“Sleepiness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/sleepiness. Accessed 20 Jan. 2026.
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