/ Dictionary / Index R r.f.b.: Meaning and Definition of Find definitions for: r.f.b. Pronunciation: [key] — Football. Football. right fullback. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. R factor RFC Related Content Daily Word Quiz: philtrum Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language