mucus
C2Pronunciation
UK
- /mjˈuːkəs/
US
- /ˈmjukəs/
Description
- Slippery fluid
- Protective barrier
- Nasal secretion
- Body lubricant
Mucus is not very glamorous, but it is very important. It is the slippery substance your nose makes when you have a cold, but it does much more than that. Mucus lines parts of your body such as your nose, throat, lungs, and digestive system. It helps trap dust, germs, and other irritants, and it keeps these areas moist so they do not dry out. When you are sick, your body often makes more mucus to help catch and remove harmful things, which can make you feel blocked up. Even when you feel healthy, your body is quietly making it all the time to help protect you.
Mucus is a gel-like substance produced by mucous membranes throughout the body. Most people think of it when they have a runny nose during cold or flu season, but it is always at work and plays an important role in keeping the body healthy. It is made mostly of water, salts, proteins, immune substances such as antibodies, and mucins, which are the proteins that give it its slippery, stretchy texture.
Its primary function is mechanical protection. It keeps delicate tissues from drying out and acts as a filter, trapping harmful particles like dust, pollen, viruses, and bacteria before they can cause damage. Tiny, hair-like structures called cilia then sweep this mucus—and the "nasties" trapped within it—toward the throat to be swallowed or expelled, effectively clearing the airways.
Mucus is not just a sign of illness; it is always present in a healthy body. However, changes in its color, thickness, or amount can sometimes show that something is going on in the body. Clear mucus is common, while thicker yellow or green mucus may appear when the immune system is fighting an infection. Beyond the breathing system, mucus also helps food move through the digestive tract and protects the stomach lining from strong acid. It also has roles in other parts of the body, including the reproductive system. In the end, mucus is a quiet but important part of human health, working in the background to protect and support the body every day.
Examples
- 1
Common cold
There was a lot of mucus in his nose after the cold.
- 2
Coughing
The doctor asked whether she was coughing up mucus.
Pattern
cough up mucus
bring mucus from the throat or lungs into the mouth
- 3
Color and texture
Clear mucus is usually less worrying than thick green mucus.
- 4
Chest congestion
Drink plenty of water to help loosen the mucus in your chest.
- 5
Stomach lining
A thin layer of mucus helps protect the stomach lining.
Forms and spellings
1 form open this card.
Main spelling
- mucusnoun