Pleura \Pleu"ra\, n.; pl. L. {Pleur[ae]}, E. {Pleuras}. [NL., n.
fem., fr. Gr. ? a rib, the side.]
1. (Anat.)
(a) The smooth serous membrane which closely covers the
lungs and the adjacent surfaces of the thorax; the
pleural membrane.
(b) The closed sac formed by the pleural membrane about
each lung, or the fold of membrane connecting each
lung with the body wall.
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2. (Zool.) Same as {Pleuron}.
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