/ Dictionary / Index O omni-: Meaning and Definition of Find definitions for: omni- Pronunciation: [key] a combining form meaning “all,” used in the formation of compound words: omnifarious; omnipotence; omniscient. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. omn. hor. omnia mutantur, nos et mutamur in illis* Related Content Daily Word Quiz: fabricate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language