mucus

noun

mu·​cus ˈmyü-kəs 

: 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

Snail goo One of the more artful shots in Wuthering Heights features the clearish mucus of a snail trailing along a window. —Fran Hoepfner, Vulture, 16 Feb. 2026

Sunbeams through the windows illuminate floating dust motes—and, imperceptibly, microdroplets of mucus carrying the measles virus, expelled from an infected but asymptomatic child who is hopping and laughing among the others. —Elizabeth Bruenig, The Atlantic, 12 Feb. 2026

Inhaling the steam from and consuming a hot beverage (like water) can help with nasal congestion by breaking up mucus and unclogging the sinuses. —Cristina Mutchler, Verywell Health, 9 Feb. 2026

Transmission occurs through saliva and mucus during close or prolonged contact, such as sharing drinks, kissing, or being exposed to coughs and sneezes. —Kelly McGreal, FOXNews.com, 1 Feb. 2026

Word History

Etymology

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-.

First Known Use

1597, in the meaning defined above

Rhymes for mucus

• fucus
• mucous
• caducous
• sambucus
• submucous
• verrucous

Kids Definition

mucus

noun

mu·​cus ˈmyü-kəs 

: a slippery sticky substance produced especially by mucous membranes which it moistens and protects

Medical Definition

mucus

noun

mu·​cus ˈmyü-kəs 

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