/ Dictionary / Index O oleo: Meaning and Definition of Find definitions for: o•le•o Pronunciation: (ō'lē-ō"), [key] — n. margarine. oleo- Pronunciation: [key] a combining form meaning “oil,” used in the formation of compound words: oleograph. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: oleo (Thesaurus) olein oleograph Related Content Daily Word Quiz: arid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language