emphysema
noun [ U ] uk/ˌem.fəˈsiː.mə/ us/ˌem.fəˈsiː.mə/
肺气肿
a condition in which the small sacs (= spaces) in the lungs become filled with too much air, causing breathing difficulties and heart problems
Heavy cigarette smoking often causes emphysema. 抽烟过多常常导致肺气肿。