/ Dictionary / Index L lumbo-: Meaning and Definition of Find definitions for: lumbo- Pronunciation: [key] a combining form meaning “loin,” used in the formation of compound words: lumbosacral. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. lumberyard lumbosacral Related Content Daily Word Quiz: hedonist Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language