The pulmonary collapse that occurs due to a space-occupying intrathoracic process such as pneumothorax or hydrothorax. ... (05 Mar 2000) ... 
relaxation atelectasis.
Type: Term Definitions: 1. the pulmonary collapse that occurs due to a space-occupying intrathoracic process such as pneumothorax or hydrothorax. Synonyms: relaxation atelectasis