1. respiratory failure of sudden onset in adults or children that follows injury to the endothelium of the lung (as in sepsis, chest trauma, massive blood transfusion, aspiration of the gastric contents, or pneumonia) and results in the accumulation of protein-rich fluid and the collapse of alveoli leading to difficult, rapid breathing and very low levels of oxygen in the blood —abbreviation ARD — called also adult respiratory distress syndrome

2. respiratory failure of sudden onset in adults or children that follows injury to the endothelium of the lung (as in sepsis, chest trauma, massive blood transfusion, aspiration of the gastric contents, or pneumonia) with the accumulation of protein-rich fluid and the collapse of alveoli leading to difficult, rapid breathing and very low levels of oxygen in the blood
The acute respiratory distress syndrome (ARDS) has been recognized for more than 30 years as a severe form of acute respiratory failure. Patients with this disorder are critically ill, require mechanical ventilation in an intensive care unit (ICU), and have a high mortality, ranging from 35% to 50% in recent reports.
— Harriet Kitzman et al., The Journal of the American Medical Association, 19 Apr. 2000 A relatively simple method of improving oxygenation in a patient with acute respiratory distress syndrome … is to place the patient in the prone position
— James W. Leatherman et al., Scientific American Medicine Bulletin, May 1997 —abbreviation ARDS — called also adult respiratory distress syndrome