mucus

American  

[myoo-kuhs] / ˈmyu kəs /

noun

1. a viscous, slimy mixture of mucins, water, electrolytes, epithelial cells, and leukocytes that is secreted by glands lining the nasal, esophageal, and other body cavities and serves primarily to protect and lubricate surfaces.

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mucus British  

/ ˈmjuːkəs /

noun

1. the slimy protective secretion of the mucous membranes, consisting mainly of mucin

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mucus Scientific  

/ myo̅o̅′kəs /

1. The slimy, viscous substance secreted as a protective lubricant by mucous membranes. Mucus is composed chiefly of large glycoproteins called mucins and inorganic salts suspended in water.

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mucus Cultural  

1. A slippery and somewhat sticky fluid secreted by the glands in mucous membranes. Mucus lubricates and protects the mucous membranes.

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Etymology

Origin of mucus

1655–65; < Latin mūcus snot; akin to Greek myktḗr nose, mýxa slime

Compare meaning

How does mucus compare to similar and commonly confused words? Explore the most common comparisons:

• sputum vs. mucus

Example Sentences

Born with cystic fibrosis, a genetic disorder that causes mucus to become thick and sticky, she has just 9% lung function.

From BBC • Mar. 24, 2026

CF is a genetic condition that can particularly affect someone's digestive system, as well as their lungs, because their body produces a thick, sticky mucus that coats the organs.

From BBC • Mar. 20, 2026

When intelectin-2 attaches to these mucins, it links them together and strengthens the mucus barrier that protects the intestinal lining.

From Science Daily • Mar. 16, 2026

Instead of focusing only on gut movement, future therapies may aim to protect the colon's mucus barrier and address the underlying microbial cause.

From Science Daily • Feb. 19, 2026

Blowflies droned about them, from time to time settling on the mucus dribbling from their noses into their mouths.

From "Kaffir Boy: An Autobiography" by Mark Mathabane

Related Words

• goo
• gunk
• mud
• sludge