Bronchiectasis is a lung condition that affects the breathing tubes or airways in your lungs. If you have bronchiectasis, the walls of the airways become wider and damaged due to inflammation or infection. You also will have more phlegm (also called mucus or sputum). This phlegm can be harder to cough out, and if it is not cleared properly it may lead to more infections and damage. Bronchiectasis may be only in one or two areas in the lungs, or it may be in many areas of the lungs
Illustration courtesy of National Heart, Lung and Blood Institute (US).