From Longman Dictionary of Contemporary Englishiron lungˌiron ˈlung noun [countable] a large machine with a metal case used to help people to breathe
Examples from the Corpus
iron lung• In my imagination and nightmares I have done time in an iron lung.• Better had I been traveling with an iron lung.• She went quickly; by afternoon, she was in the iron lung and she died the next morning.• The iron lung encased Virginia in a vacuum.