What underlying condition(s) does your husband have that have led to repeated x-rays?

Here is what "ground glass" means in an x-ray interpretation by a radiologist: A hazy gray or whitish appearance in the lungs so underlying features look indistinct, as though your were looking through a frosted glass window. It is terminology they use so the doctor and radiologist both understand what the image shows.
What does it mean? It often indicates fluid or artifacts left behind after an infection such as pneumonia or Covid. The doctor's task is to put that description together with whatever other tests, symptoms and observations they have to reach a diagnosis.

Here is what a "nodule" means in the same context: A nodule is a small solid white or gray mass less than 3cm (1.18 in) in diameter which is rarely cancerous. These may be caused by an infection, an autoimmune disease like sarcoidosis, exposure to asbestos or air pollution, or even smoking. About half the adult population has these. Again, it is the doctor's task to use this as one piece of a diagnosis puzzle.

If ground glass opacities or small nodules are discovered incidentally, during imaging for another reason, the usual procedure is to monitor them every 6 months for a year or two to see whether they are stable, growing, or shrinking.

If the person has other indications of underlying lung issues like a chronic cough, COPD, Emphysema, Asthma, Chronic Bronchitis or Bronchiectasis further imaging and testing will usually be done to determine the best treatment.

Is your husband a current or former smoker, or has he recently had Covid, pneumonia or a lung infection?
What does his doctor say?