mediastinum

noun

me·​di·​as·​ti·​num ˌmē-dē-ə-ˈstī-nəm 

plural mediastina ˌmē-dē-ə-ˈstī-nə 

: 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

ˌmē-dē-ə-ˈstī-nᵊl 

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 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

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

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

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

Medical Definition

mediastinum

noun

me·​di·​as·​ti·​num ˌmēd-ē-ə-ˈstī-nəm 

plural mediastina -nə 

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

: mediastinum testis