Definition & Meaning of "mucus"

What is "mucus"?

Mucus is a viscous and slippery substance produced by the mucous membranes lining various organs and passages. It acts as a protective and lubricating layer, particularly in the respiratory and digestive systems. Mucus helps to trap and remove foreign particles, such as dust and pathogens, preventing them from reaching sensitive tissues. In the respiratory system, mucus plays a vital role in moistening and protecting the airways, facilitating efficient breathing. In the digestive system, mucus aids in the smooth passage of food and protects the stomach lining from digestive acids. Mucus production can increase during illness or inflammation, leading to symptoms like congestion or a runny nose.