/ Dictionary / Index L lbf: Meaning and Definition of Find definitions for: lbf Pronunciation: [key] pound-force. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. lb. av. LBJ Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language