Variant of mediastinum
noun pl. mediastina
- a membranous partition between two cavities of the body, esp. that separating the lungs or the two pleural sacs
- the space between the pleural sacs, containing the heart and other chest viscera except the lungs
Origin: ModL < ML mediastinus, in the middle (form infl. by L mediastinus, servant, medical assistant) < L medius, middle: see mid
- mediastinal adjective
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