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