- 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.
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 medius mid1, though sense and formation unclear
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Examples from the Web for mediastinum
It has been known to descend along the planes of connective tissue into the mediastinum or into the lungs.
The subcutaneous tissue, pericardium, mediastinum, and mesenterium contained considerable amounts of fat.Plague
Thomas Wright Jackson
Several lymphatic glands in the anterior part of the mediastinum contained black fluid.An Investigation into the Nature of Black Phthisis
This is a point of great practical importance in determining the extension of inflammation into the mediastinum.
- 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
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
- An abnormal presence of chyle in the mediastinum.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.