SLEEPINESS Synonyms: 21 Similar and Opposite Words

sleepiness

noun

Definition of sleepiness

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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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 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 The clinical data demonstrated significant improvements in wakefulness and reductions in excessive daytime sleepiness at week eight, outperforming the placebo with a generally favorable safety profile. — Sasirekha Subramanian, Forbes.com, 29 June 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 Researchers also observed improvements in sleep maintenance and reductions in daytime fatigue, anxiety, depression symptoms and daytime sleepiness. — Samantha Agate, Kansas City Star, 7 May 2026 Researchers measured insomnia severity using the Insomnia Severity Index, along with sleep maintenance, daytime sleepiness, fatigue, anxiety and depression symptoms. — Samantha Agate, Charlotte Observer, 7 May 2026 Mention any daytime symptoms, such as excessive sleepiness or headaches, and any nighttime symptoms, such as frequent urination, waking up short of breath, snoring or insomnia. — Erika Yamazaki, The Conversation, 6 May 2026

Recent Examples of Synonyms for sleepiness

Noun

Some symptoms of diphenhydramine poisoning include drowsiness, agitation, fast heart rate, nausea, vomiting, hallucinations, seizures, dangerous heart rhythm and loss of consciousness.

— Angelica Stabile, FOXNews.com, 19 June 2026
It is also known to cause side effects, including drowsiness, sedation and dizziness.

— Mary Walrath-Holdridge, USA Today, 12 June 2026

Definition of drowsiness

Noun

But markets are showing signs of fatigue, after absorbing this flood of debt in such a short time, S&P warned, pointing out that hyperscalers are now paying a higher premium compared with yields on risk-free bonds.

— Jason Ma, Fortune, 31 July 2026
The economic difficulties, energy blackouts, Internet restrictions, and general wartime fatigue have pushed Putin’s approval ratings from around 80 percent at the beginning of the year to 66 percent in mid-July.

— Alexander Gabuev, Foreign Affairs, 31 July 2026

Definition of fatigue

Noun

After two moves in less than a year, Joni Moreland’s efforts to find a new home for her nonprofit — which provides free clothes, hygiene products, groceries, dog beds and sleeping mats for residents in need of assistance — is far from over.

— Taylor O'Connor July 29, Kansas City Star, 29 July 2026
Your sleeping position is also important; for example, for those who can manage it, sleeping on your back with your head slightly elevated is a excellent for your skin, and helps prevent fluid from pooling under your eyes.

— Laura Sandroni, Vogue, 29 July 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

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sleep in

sleepiness

sleeping

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“Sleepiness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/sleepiness. Accessed 4 Aug. 2026.

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Synonyms of sleepiness

noun

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