What is the common name for the condition known as pneumothorax?

Pneumothorax is commonly referred to as a "collapsed lung." This condition occurs when air enters the space between the lungs and the chest wall, leading to a partial or complete collapse of the lung on the affected side. The presence of air in this pleural space disrupts the normal pressure dynamics necessary for lung expansion during breathing, which is why it is often associated with the term "collapsed lung."

Understanding this terminology is crucial, especially in medical settings, as it helps in identifying the condition quickly for effective treatment. Recognizing pneumothorax as a collapsed lung can guide healthcare professionals in delivering timely interventions to re-expand the lung and restore normal respiration. The other options describe different respiratory conditions and symptoms but do not directly address the physiological state defined by pneumothorax.