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

Mediastinum, mē-di-as-tī′num, n. a membranous septum or cavity between two principal portions of an organ, esp. the folds of the pleura and the space between the right and left lungs.—adj.

From Chambers's Twentieth Century Dictionary (part 2 of 4: E-M) by Various