mu·​cus | \ ˈmyü-kəs How to pronounce mucus (audio) \

Definition of mucus

: a viscid slippery secretion that is usually rich in mucins and is produced by mucous membranes which it moistens and protects

Examples of mucus in a Sentence

Recent Examples on the Web Those with no symptoms had increased levels of B cells, which produce antibodies found in the nose and other mucus passages. Evan Macdonald, cleveland, "CDC finds limited, mild cases among vaccinated; study finds different immune response based on symptoms: Coronavirus update for April 22, 2021," 22 Apr. 2021 In the context of an embryo, the stem cells would have grown cilia, tiny hairlike cells that allow mucus to cover frog skin. Erin Blakemore Washington Post, Star Tribune, "Biologists' work on stem cells and 'xenobots' alters our views about how organisms are built," 22 Apr. 2021 Sinus rinses like neti pots can help wash out mucus, especially when people use hypertonic saline, Dass said. Slone Terranella, Detroit Free Press, "Seasonal allergies kicking your butt? Here's why it's one of the worst allergy seasons," 19 Apr. 2021 Chloride’s negative charge attracts water, so without much chloride meandering into cells, the body’s mucus gets thicker and stickier, making breathing a struggle and often trapping dangerous bacteria in the lungs. Max G. Levy, Wired, "This Sticker Absorbs Sweat—and Might Diagnose Cystic Fibrosis," 8 Apr. 2021 Humidifiers also aid in loosening mucus if your little one has a cold or sore throat. Bre Richey,, "The best humidifier for babies," 2 Apr. 2021 Haley plays 17-year-old Stella who has cystic fibrosis, a condition that means the body produces thick mucus that can block air to the lungs. Kori Williams, Seventeen, "50 Best Romantic Movies of All Time to Stream Now," 9 Mar. 2021 The drug has been around since the 1960s when it was introduced as an agent for clearing mucus in the lungs and later as an antidote for acetaminophen poisoning. Cezary Podkul, WSJ, "How to Stop Biting Your Nails—a Potential Treatment Offers Promise," 28 Dec. 2020 The heat also helps to break down and thin out mucus to help clear it from the body. Morgan Hines, USA TODAY, "Can a hot toddy really help relieve cold symptoms? Experts say yes — sort of," 23 Dec. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mucus.' 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 mucus

1597, in the meaning defined above

History and Etymology for mucus

borrowed from Latin mūcus, muccus "nasal discharge," perhaps going back to *moukos, o-grade derivative of Indo-European *(s)muk- "nasal discharge," *(s)meuk- "undo, loosen, wipe off" — more at myxo-

Note: See note at myxo-.

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Statistics for mucus

Last Updated

28 Apr 2021

Cite this Entry

“Mucus.” Dictionary, Merriam-Webster, Accessed 12 May. 2021.

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More Definitions for mucus



English Language Learners Definition of mucus

: a thick liquid that is produced in some parts of the body (such as the nose and throat)


mu·​cus | \ ˈmyü-kəs How to pronounce mucus (audio) \

Kids Definition of mucus

: a slippery thick sticky substance that coats, protects, and moistens the linings of body passages and spaces (as of the nose, lungs, and intestines)


mu·​cus | \ ˈmyü-kəs How to pronounce mucus (audio) \

Medical Definition of mucus

: a viscid slippery secretion that is usually rich in mucins and is produced by mucous membranes which it moistens and protects

More from Merriam-Webster on mucus

Nglish: Translation of mucus for Spanish Speakers

Britannica English: Translation of mucus for Arabic Speakers Encyclopedia article about mucus

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