Entry 1 sense Webster, 1913 Pleural /plo͝or'-əl/ · Pleu·ral · IPA /ˈplʊɹ.əl/ 01 a. Of or pertaining to the pleura or pleuræ, or to the sides of the thorax. 1. Of or pertaining to the pleura or pleuræ, or to the sides of the thorax.(Anat.)