/ Dictionary / Index R rapidly advancing juvenile periodontitis: Meaning and Definition of Find definitions for: rap'idly advanc'ing ju'venile periodonti'tis Pronunciation: [key] — Dentistry. Dentistry. a rare, rapidly progressive and destructive infectious periodontal disease that usually affects the front teeth and first permanent molars of children. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. rapidity rapido Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language