pleu·ra 1   (plŏŏr'ə)    n.   pl. pleu·rae (plŏŏr'ē) A thin serous membrane in mammals that envelops each lung and folds back to make a lining for the chest cavity. [Middle English, from Medieval Latin, from Greek, side, rib.] pleu'ral adj.

Main Entry: pleu·ra
Pronunciation: 'plur-&
Function: noun
Inflected Form: plural pleu·rae /'plur-E/ or pleuras
: either of a pair of two-walled sacs of serous membrane each of which lines one lateral half of the thorax, has an inner layer closely adherent to the corresponding lung,is reflected at the root of the lung to form a parietal layer that adheres to the walls of the thorax, the pericardium, the upper surface of the diaphragm, and adjacent parts, and contains a smallamount of serous fluid that minimizes the friction of respiratory movements

pleura pleu·ra (pl&oobreve;r'ə)
n. pl. pleu·rae (pl&oobreve;r'ē)
The thin serous membrane that envelops each lung and folds back to make a lining for the chest cavity.

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pleu'ral adj.

pleura

membrane lining the thoracic cavity (parietal pleura) and covering the lungs (visceral pleura). The parietal pleura folds back on itself at the root of the lung to become the visceral pleura. In health the two pleurae are in contact. When the lung collapses, however, or when air or liquid collects between the two membranes, the pleural cavity or sac becomes apparent (see pleurisy). There are actually two pleural cavities, the right and the left; each constitutes a closed unit not connected to the other. The glistening surface of the pleura is made up of a sheet of flat cells, the mesothelium, which covers an underlying layer of loose elastic tissue. The pleura exudes a thin fluid that keeps it moist and lubricated.

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