mediastinum

noun

me·​di·​as·​ti·​num ˌmē-dē-ə-ˈstī-nəm How to pronounce mediastinum (audio)
plural mediastina ˌmē-dē-ə-ˈstī-nə How to pronounce mediastinum (audio)
: the space in the chest between the pleural sacs of the lungs that contains all the tissues and organs of the chest except the lungs and pleurae
also : this space with its contents
mediastinal adjective

Examples of mediastinum in a Sentence

Recent Examples on the Web According to the Dana-Farber Cancer Institute, this type of cancer usually starts in the upper chest area called the mediastinum. Jordan Greene, Peoplemag, 23 Apr. 2024 The mediastinum of your body is a space that keeps your lungs and other chest structures (e.g., heart, esophagus, windpipe) separate.4 For example, two 2020 studies found that patients had swollen lymph nodes in the mediastinum area. Korin Miller, Health, 25 Sep. 2023 The swollen lymph nodes in the mediastinum were also associated with a higher risk of admission to an intensive care unit (ICU). Korin Miller, Health, 25 Sep. 2023 There was now significant air in the space between his lungs, known as the mediastinum, which had tracked up into his neck under the skin. Douglas G. Adler, Discover Magazine, 14 Dec. 2021 The mediastinum is ordinarily a sterile space, but easily becomes infected when an esophageal rupture occurs. Douglas G. Adler, Discover Magazine, 14 Dec. 2021 Based on the CT scan results, Matt’s mediastinum only seemed to have air in it and did not look to be infected just yet. Douglas G. Adler, Discover Magazine, 14 Dec. 2021 If leaked into the trachea, these contents could have led to pneumonia, or if into the mediastinum, to sepsis and vascular collapse. W Roy Smythe, Discover Magazine, 4 Oct. 2011 Limited-stage disease is used to describe lung cancer that’s only found within one lung, and may be found in the mediastinum between the lungs. Amanda MacMillan, Health.com, 23 July 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'mediastinum.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

New Latin, from Medieval Latin, neuter of mediastinus medial, from Latin medius

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of mediastinum was in the 15th century

Dictionary Entries Near mediastinum

Cite this Entry

“Mediastinum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mediastinum. Accessed 5 Oct. 2024.

Medical Definition

mediastinum

noun
me·​di·​as·​ti·​num ˌmēd-ē-ə-ˈstī-nəm How to pronounce mediastinum (audio)
plural mediastina -nə How to pronounce mediastinum (audio)
1
: the space in the chest between the pleural sacs of the lungs that contains all the viscera of the chest except the lungs and pleurae
also : this space with its contents
2

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