[ mee-dee-a-stahy-nuhm ]
/ ˌmi di æˈstaɪ nəm /
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noun, plural me·di·as·ti·na [mee-dee-a-stahy-nuh]. /ˌmi di æˈstaɪ nə/. Anatomy.
a median septum or partition between two parts of an organ, or paired cavities of the body.
the partition separating the right and left thoracic cavities, formed of the two inner pleural walls, and, in humans, comprising all the viscera of the thorax except the lungs.
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Origin of mediastinum

1535–45; <New Latin; compare mediastīnus of middle class, apparently identical with Latin mediast(r)īnus a low-ranking slave, perhaps derivative of mediusmid1, though sense and formation unclear

OTHER WORDS FROM mediastinum

me·di·as·ti·nal, adjective
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How to use mediastinum in a sentence

British Dictionary definitions for mediastinum

/ (ˌmiːdɪəˈstaɪnəm) /

noun plural -na (-nə) anatomy
a membrane between two parts of an organ or cavity such as the pleural tissue between the two lungs
the part of the thoracic cavity that lies between the lungs, containing the heart, trachea, etc

Derived forms of mediastinum

mediastinal, adjective

Word Origin for mediastinum

C16: from medical Latin, neuter of Medieval Latin mediastīnus median, from Latin: low grade of servant, from medius mean
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for mediastinum

[ mē′dē-ə-stīnəm ]

n. pl. me•di•as•ti•na (-nə)
A septum between two parts of an organ or a cavity.
The region in mammals between the pleural sacs, containing the heart and all of the thoracic viscera except the lungs.interpleural space mediastinal space

Other words from mediastinum

me′di•as•tinal (-nəl) adj.me′di•as•tinal•ly adv.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.