Definition:
Mucus is a slippery liquid that is made by glands in the mucous membranes that line the mouth, nose, throat, lungs, breathing passageways, digestive organs, and reproductive organs. Mucus is slippery because it contains a lubricant called mucin. Mucus also contains cells, salt, and water.
The purpose of mucus is to lubricate and protect the organs that it lines. Mucus is supposed to be thin, clear, and watery. Cloudy, yellow, or green mucus are signs of an infection.
In cystic fibrosis, mucus is not thin and watery. It is thick and sticky. Instead of lubricating and protecting the organs, it clogs them up.
Pronunciation: myou-kus
Also Known As: phlegm, sputum
Common Misspellings: Mucous, which is a legitimate word but it means "something that contains mucus". For example, "mucous membranes"
