Abnormally viscid mucus secreted by the mucosa of the respiratory passages during certain infectious processes.
Catarrhal secretion or sputum.
Thick slimy mucus produced in the respiratory passage.
Thick mucus of the respiratory passages.
Viscous, stringy mucus secreted by the walls of the respiratory tract.
Thickened excess mucus that may accumulate in the throat or chest when the nose, sinus, and bronchi are inflamed, as occurs when a person has a common cold. Phlegm may also develop in response to exposure to chemicals, pollution, cigarette smoke, or the presence of a more severe infection. It can also occur with chronic bronchitis. The excess mucus can accumulate in the lungs and clog the smaller airways, called bronchial tubes, making breathing difficult and contributing to infections in the respiratory tract.