/ Dictionary / Index P pyelonephritis: Meaning and Definition of Find definitions for: py•e•lo•ne•phri•tis Pronunciation: (pī"u-lō-nu-frī'tis, pī-el"ō-), [key] — n. Pathol. inflammation of the kidney and its pelvis, caused by a bacterial infection. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: pyelonephritis (Thesaurus) pyelography pyelonephrosis Related Content Daily Word Quiz: deleterious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language