/ Dictionary / Index P pneumonia: Meaning and Definition of Find definitions for: pneu•mo•nia Pronunciation: (noo-mōn'yu, -mō'nē-u, nyoo-), [key] — n. Pathol. inflammation of the lungs with congestion. Also calledan acute disease of the lungs, caused by the bacterium Streptococcus pneumoniae and characterized by fever, a cough with blood-tinged phlegm, and difficult breathing. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: pneumonia (Thesaurus) pneumonectomy pneumonic Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language