/ Dictionary / Index R ricinus oil: Meaning and Definition of Find definitions for: ric'i•nus oil" Pronunciation: (ris'u-nus), [key] — Chem. Chem. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ricinolein rick Related Content Daily Word Quiz: censure Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language