ENGLISH
REFERENCE

mucus

n. uncountable
C1 Advanced US //ˈmjukəs// UK //mjˈuːkəs// mu·cus

n. a thick, slippery liquid that your body makes to protect and clean parts like your nose and throat.

n. a viscous, slippery secretion produced by mucous membranes that serves to protect and lubricate surfaces within the body.


SIMPLE

Mucus helps protect your lungs from dust.

CONTEXTUAL

When you have a cold, your body produces extra mucus to help trap and remove germs from your system.

COMPLEX

The respiratory system relies on a thin layer of mucus to capture inhaled particulates, which are then cleared by the rhythmic beating of microscopic cilia.

Origin

Learned borrowing from Latin mūcus. Partly displaced Old English slīm, whence modern slime.

Usage

Uncountable in its general biological sense; occasionally used as a countable noun in medical contexts to refer to specific types or samples.

Pitfall

He has a lot of mucous.He has a lot of mucus.Learners often confuse the noun 'mucus' with the adjective 'mucous' (as in 'mucous membrane').

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