phlegm

If someone says you sound "phlegmy," it means you have thick mucus in your throat or chest, often during a cold or chest infection. It is the heavy, sticky stuff that you may need to cough up so you can breathe more easily. In older medicine, "phlegm" was also the name of one of the four humors, and people believed too much of it could make someone calm and unemotional. Today, though, the word is mainly used for the mucus itself. You might hear sentences like, "He's been coughing up a lot of phlegm," or "Her voice sounded thick with phlegm."

Phlegm is a specific type of thick mucus made in the respiratory tract, especially in the lungs, bronchi, throat, and other airways. The body normally makes some mucus to keep these tissues moist and to trap dust, germs, and other particles. When there is irritation, inflammation, or infection, the body may produce more of it, and that thicker mucus is often called phlegm. It commonly appears with colds, the flu, bronchitis, pneumonia, allergies, smoking, or other conditions that affect breathing. It is often clear or white, but it can also look yellow or green when the body is reacting to illness.

The word "phlegm" also has a long medical history. It comes from the Greek word phlegma, meaning "inflammation," and it was one of the four humors in ancient Greek and Roman medicine. Doctors at the time believed that these four humors shaped both health and personality. In that older way of thinking, a "phlegmatic" person was calm, steady, and not very emotional.

Today, we use the term in a more direct way to describe the thick mucus that people cough up during a chest cold or other breathing illness. It often comes up with symptoms such as congestion, a wet cough, or a sore throat. You might hear a doctor talk about coughing up phlegm or recommend medicine that helps loosen it. Knowing the difference between general mucus and phlegm can help you describe your symptoms more clearly.