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

Instead, chloride seemed to get stuck inside their cells, which was drawing water out of the airways and out of the lungs’ normally fluid mucus. —Courtney Crowder, USA Today, 18 Apr. 2026

This condition, sometimes called nonallergic rhinitis, occurs as older bodies lose some control over blood vessels in the nose and mucus glands. —Matt Fuchs, Scientific American, 15 Apr. 2026

Symptoms include coughing up blood or mucus, weight loss, chest pain, chills and fever, according to the Mayo Clinic. —Ingrid Vasquez, PEOPLE, 14 Apr. 2026

Elevating your head with pillows or sleeping on your side can lessen the feelings of congestion that often plague allergy sufferers by allowing mucus to drain instead of pool. —Helen Carefoot, Flow Space, 14 Apr. 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