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 Digital pharmacy firm Capsule has teamed up with Virtuwell, which helps serve more than one million patients with common conditions such as pink eye and sinus infections, among others, to create a joint digital care platform. Sy Mukherjee, Fortune, "The sad science of pandemic grief," 19 Nov. 2020 At an urgent care clinic, a doctor diagnosed a sinus infection but didn’t test for covid-19. Washington Post, "America’s 250,000 covid deaths: People die, but little changes," 18 Nov. 2020 According to a person familiar with the matter, a male volunteer in his twenties had a cerebral hemorrhage and transverse sinus venous thrombosis. Matthew Herper, STAT, "Covid-19 vaccine trials from AstraZeneca, Johnson & Johnson to restart," 23 Oct. 2020 In late 2017, Layla began having breathing problems and was diagnosed with sinus obstructions. Graydon Megan, chicagotribune.com, "A boy and the black rhino isn’t a children’s book: Elmhurst toddler bonds with Brookfield Zoo veterinarian caring for endangered animal," 20 Oct. 2020 In light of all this Dr Lebeer wonders if L. casei AMBR2 might be used as a treatment for chronic sinus conditions. The Economist, "Nasal probiotics The nose, it seems, is protected by bacterial guards," 13 June 2020 Last year, my 20-year-old sister, Nia Phillips, suffered a rare type of stroke known as venous sinus thrombosis as a direct result of taking Rigevidon. Jessica Phillips, refinery29.com, "I Had A Stroke At 20 Because Of The Pill," 29 Sep. 2020 Williams went to the doctor on Sept. 8 because of a sinus infection. Dennis Victory, al, "COVID-19 affects volleyball programs, too; Huntsville High will miss postseason," 2 Oct. 2020 There’s a risk of bacterial pneumonia, ear and sinus infections, and worsening of chronic diseases like diabetes, heart disease and asthma. NBC News, "5 reasons why this is the most important flu shot of your lifetime," 28 Sep. 2020

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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Statistics for sinus

Last Updated

22 Nov 2020

Cite this Entry

“Sinus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sinus. Accessed 29 Nov. 2020.

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More Definitions for sinus

sinus

noun
How to pronounce sinus (audio)

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

Comments on sinus

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