In medical terminology, gross means something that can be seen with the unaided eye, so without magnification. Grossly clear lungs means that by whatever imaging they used, the lungs appeared clear. It is not saying that there isn't any microscopic stuff there, but there is't enough to see without magnification.

Chronic obstructive pulmonary disease also called COPD is typically caused by chronic smoking making the patient difficult to breathe. The airways in the lung are narrowed due to inflammation and damage, with an increase in production of mucus. The appearance of the lungs however depends on the severity of the disease. In an X-ray of a patient with COPD the lungs typically appear more whiter than the lungs of a normal person with decreased air spaces (black/dark spaces) indicating narrow air ways. In a CT the lungs show diffuse hazy pattern with mosaic appearance due to small airways with thick walled bronchi.

If your lungs do not sound clear, and your doctor detects an abnormal breathing sound, the next step is to undergo testing to identify the cause. Digital pulse oximetry is a painless, noninvasive method of measuring the saturation of oxygen in your blood.

On an X-ray, 'clear lungs' means that the lungs are normally aerated (filled with air) and there is no visible mass, pneumonia, or areas of decreased aeration. HealthTap's Answers from Doctors is created for people with ongoing healthcare needs but benefits everyone.