/ Dictionary / Index O olefiant gas: Meaning and Definition of Find definitions for: o•le•fi'ant gas' Pronunciation: (ō"lu-fī'unt, ō-lē'fē-, ō-lef'ē-), [key] ethylene (def. 2). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. olecranon olefin Related Content Daily Word Quiz: longevity Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language