NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,846 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- listen (A-teh-LEK-tuh-sis)
- Failure of the lung to expand (inflate) completely. This may be caused by a blocked airway, a tumor, general anesthesia, pneumonia or other lung infections, lung disease, or long-term bedrest with shallow breathing. Sometimes called a collapsed lung.