mediastinum

American  

[mee-dee-a-stahy-nuhm] / ˌmi di æˈstaɪ nəm /

noun

Anatomy.

plural

mediastina

1. a median septum or partition between two parts of an organ, or paired cavities of the body.

2. 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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mediastinum British  

/ ˌmiːdɪəˈstaɪnəm /

noun

1. a membrane between two parts of an organ or cavity such as the pleural tissue between the two lungs

2. the part of the thoracic cavity that lies between the lungs, containing the heart, trachea, etc

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Other Word Forms

• mediastinal adjective

Etymology

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 mid ¹, though sense and formation unclear

Example Sentences

The right and left pleurae, which enclose the right and left lungs, respectively, are separated by the mediastinum.

From Textbooks • Jun. 19, 2013

The lungs are enclosed by the pleurae, which are attached to the mediastinum.

From Textbooks • Jun. 19, 2013

Figure 19.2 Position of the Heart in the Thorax The heart is located within the thoracic cavity, medially between the lungs in the mediastinum.

From Textbooks • Jun. 19, 2013

Within the mediastinum, the heart is separated from the other mediastinal structures by a tough membrane known as the pericardium, or pericardial sac, and sits in its own space called the pericardial cavity.

From Textbooks • Jun. 19, 2013

Examination in the afternoon of March 21.—On removing the sternum and anterior portion of the ribs, the anterior mediastinum was found filled with a frothy adipo-mucous collection of a yellowish colour.

From North American Medical and Surgical Journal, Vol. 2, No. 3, July, 1826 by Bache, Franklin