/ Dictionary / Index P pleural cavity: Meaning and Definition of Find definitions for: pleu'ral cav'ity Pronunciation: [key] a narrow, fluid-filled space between the pleural membranes of the lung and the inner chest wall. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. pleural pleurisy Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language