sinus

noun
si·​nus | \ ˈsī-nəs How to pronounce sinus (audio) \

Definition of sinus

: cavity, hollow: such as
a : a narrow elongated tract extending from a focus of suppuration and serving for the discharge of pus
b(1) : a cavity in the substance of a bone of the skull that usually communicates with the nostrils and contains air
(2) : a channel for venous blood
(3) : a dilatation in a bodily canal or vessel
c : a cleft or indentation between adjoining lobes (as of a leaf or corolla)

Examples of sinus in a Sentence

Recent Examples on the Web Cold and flu season has begun and South Florida already is reeling from a virus — not COVID-19 — that is giving people runny noses, sinus infections, headaches, fatigue, coughs, sore throats, and nausea. Cindy Krischer Goodman, sun-sentinel.com, 19 Nov. 2021 Back in April, the one-shot Johnson & Johnson vaccine was briefly pulled from the market after rare cases of cerebral venous sinus thrombosis (CVST), a type of blood clot, began to occur predominantly among women ages 18-48. Nikolas Lanum, Fox News, 8 Nov. 2021 Some people might even struggle with regular sinus infections if the object blocks where the sinuses drain, Dr. McCormick says. Korin Miller, Health.com, 28 Oct. 2021 Rose, battling a sinus infection and in the middle of a move, knew that no one declines a songwriting session with Swift. Emily Yahr, Anchorage Daily News, 12 Nov. 2021 Rose, battling a sinus infection and in the middle of a move, knew that no one declines a songwriting session with Swift. Washington Post, 14 Oct. 2021 Her mother was instead diagnosed with a sinus infection. Fox News, 28 Oct. 2021 About 40% still have chronic sinus problems or acid reflux. David B. Caruso, Anchorage Daily News, 10 Sep. 2021 People with allergies, sinus problems, COPD, asthma, eczema and other conditions seek out salt room sessions to help relieve symptoms. Patrick Connolly, orlandosentinel.com, 22 Aug. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sinus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of sinus

15th century, in the meaning defined above

History and Etymology for sinus

Middle English, from Medieval Latin, from Latin, curve, fold, hollow

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Time Traveler for sinus

Time Traveler

The first known use of sinus was in the 15th century

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Dictionary Entries Near sinus

sinuous

sinus

sinus gland

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Statistics for sinus

Last Updated

4 Dec 2021

Cite this Entry

“Sinus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sinus. Accessed 8 Dec. 2021.

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More Definitions for sinus

sinus

noun

English Language Learners Definition of sinus

: any of several spaces in the skull that connect with the nostrils

sinus

noun
si·​nus | \ ˈsī-nəs How to pronounce sinus (audio) \

Kids Definition of sinus

: any of several spaces in the skull mostly connected with the nostrils

sinus

noun
si·​nus | \ ˈsī-nəs How to pronounce sinus (audio) \

Medical Definition of sinus

: a cavity or hollow in the body: as
a : a narrow elongated tract extending from a focus of suppuration and serving for the discharge of pus a tuberculous sinus
b(1) : a cavity in the substance of a bone of the skull that usually communicates with the nostrils and contains air
(2) : a channel for venous blood
(3) : a dilatation in a bodily canal or vessel

More from Merriam-Webster on sinus

Nglish: Translation of sinus for Spanish Speakers

Britannica.com: Encyclopedia article about sinus

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