"You canker blossom!" 3 Shakespearean Insults
mediastinum me·di·as·ti·num (mē'dē-ə-stī'nəm)
n. pl. me·di·as·ti·na (-nə)
A septum between two parts of an organ or a cavity.
The region in mammals between the pleural sacs, containing the heart and all of the thoracic viscera except the lungs. Also called interpleural space, mediastinal space.