What are ground glass infiltrates on an x-ray and what does that diagnosis mean?

there are two causes which i am certain to cause ground glass infiltrates, ARDS (acute respiratory distress syndrome) and a much rarer condition called Cryptogenic organising pneumonia.. ground glass infiltrates refers to involvement of both the alveoli and the pulmonary interstitium which occurs in both the conditions resulting in homogenous density film on a plain XR of the chest...