noun

mucus

MYOO-kuhs

Mucus (noun) means the slippery fluid produced by the lining of the nose, throat, lungs, gut and other internal surfaces, which keeps them moist and traps dust and germs. Example: “A cold makes the body produce far more mucus than usual.”

noun

The slippery fluid produced by the lining of the nose, throat, lungs, gut and other internal surfaces, which keeps them moist and traps dust and germs.

"A cold makes the body produce far more mucus than usual."

"Cilia sweep mucus up out of the airways."

How to use mucus

Learner’s notes

In plain EnglishThe slippery stuff your nose and throat make.

When to use it

Neutral and medical; everyday speech often uses 'snot' or 'catarrh' instead.

Memory tip

Mucus is uncountable, so say 'a lot of mucus', never 'mucuses'.

Trace the full origin ↓

Easily confused with

mucous → phlegm → catarrh

Common pairings

mucus membrane excess mucus clear the mucus thick mucus

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Fill the gap

Can you complete this real example?

A cold makes the body produce far more _____ than usual.

Etymology

From Latin mucus, meaning nasal mucus.

Origin: Latin

Rhymes for mucus

caucus

See all rhymes for mucus →

Frequently asked questions

What is the difference between mucus and mucous?

Mucus is the noun, the substance itself. Mucous is the adjective, used in phrases such as mucous membrane. If you can put 'the' in front of it, you want mucus.

What does the colour of mucus mean?

Clear mucus is normal, and thicker white or yellow mucus is common with a cold as immune cells gather in it. Green mucus is often assumed to mean a bacterial infection, but on its own it does not prove one; persistent symptoms are a better reason to see a doctor.

What is the difference between mucus and phlegm?

Phlegm is specifically the mucus produced in the lower airways and coughed up from the chest. All phlegm is mucus, but mucus from the nose or gut is not called phlegm.

What is the meaning of mucus?

"mucus" (noun) means the slippery fluid produced by the lining of the nose, throat, lungs, gut and other internal surfaces, which keeps them moist and traps dust and germs.