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