/ Dictionary / Index S sinistro-: Meaning and Definition of Find definitions for: sinistro- Pronunciation: [key] a combining form meaning “left, on the left,” used in the formation of compound words: sinistrodextral. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. sinistration sinistrocular Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language