Breadcrumb Home > Dictionary > Index R rock oil: Meaning and Definition of Find definitions for: rock' oil" Pronunciation: [key] petroleum. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Rock of Gibraltar rockoon ✖ Related Content Daily Word Quiz: donnybrook Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language