pneumomediastinum
noun
pneu·mo·me·di·as·ti·num
| \ ˌn(y)ü-mō-ˌmēd-ē-ə-ˈstī-nəm
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plural pneumomediastina\ -nə
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Medical Definition of pneumomediastinum
1
: an abnormal state characterized by the presence of gas (as air) in the mediastinum
2
: the induction of pneumomediastinum as an aid to radiography