/ Dictionary / Index T thoracentesis: Meaning and Definition of Find definitions for: tho•ra•cen•te•sis Pronunciation: (thôr"u-sen-tē'sis, thōr"-), [key] — pl. -ses insertion of a hollow needle or similar instrument into the pleural cavity of the chest in order to drain pleural fluid. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: thoracentesis (Thesaurus) thorac- thoracic Related Content Daily Word Quiz: blithesome Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language