/ Dictionary / Index O octane: Meaning and Definition of Find definitions for: oc•tane Pronunciation: (ok'tān), [key] — n. Chem. any of 18 isomeric saturated hydrocarbons having the formula CH, some of which are obtained in the distillation and cracking of petroleum. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: octane (Thesaurus) octan octane number Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language