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

Survival rates doubled with certain advanced cancers, such as those of the salivary gland, paranasal sinus, and bone sarcoma, compared with conventional radiation therapy. Michele Cohen Marill, WIRED, "Why a Promising, Potent Cancer Therapy Isn't Used in the US," 21 Aug. 2019 But people with weakened immune systems are at a higher risk of developing infections in the lungs or sinuses from the mold. CBS News, "Seattle Children's Hospital mold infections leave one dead, force closure of most operating rooms," 3 July 2019 This tends to happen when people are in splashy water parks, jet-skiing, or irrigating their sinuses with tap water that hasn’t been disinfected, boiled, or filtered. Beth Mole, Ars Technica, "Brain-eating amoeba kills again—here’s how it kills and how to avoid it," 26 July 2019 My sinuses are extremely irritated during certain times of the year and the salt room with its relaxing environment is especially beneficial to me. Deborah Storey | For Al.com, al, "Huntsville salt therapy spa part of nationwide trend," 25 July 2019 My sinuses, on the other hand, weren't feeling much better. Sarah Watts, NBC News, "Does salt therapy actually work? I tried it to help ease my summer allergies," 23 July 2019 Brother Sage is a believer in urine therapy and has practiced this technique for decades, using urine to wash his eyes, clean his feet and clear out his sinuses. Kai Beech, The Denver Post, "A urine therapy group in Colorado touts the benefits of drinking your own pee. Doctors disagree," 23 July 2019 After D'wan Mathis complained of headaches and severe sinus pain, Georgia's medical director Ron Courson recognized the signs of a cyst and rushed Mathis to the emergency room. Tess Demeyer, USA TODAY, "Father of Georgia QB D'Wan Mathis says school saved son's life with brain surgery," 12 May 2019 This type of infection often stems from an untreated sinus or ear infection. Julia Michie Bruckner, Discover Magazine, "Is a Teen's Pain Just Drama, or Something Worse?," 12 Mar. 2019

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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Statistics for sinus

Last Updated

3 Sep 2019

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Time Traveler for sinus

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

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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

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More from Merriam-Webster on sinus

Rhyming Dictionary: Words that rhyme with sinus

Spanish Central: Translation of sinus

Nglish: Translation of sinus for Spanish Speakers

Britannica.com: Encyclopedia article about sinus

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