/ Dictionary / Index O Old Irish: Meaning and Definition of Find definitions for: Old' I'rish Pronunciation: [key] the Irish language before c900. Abbr.: OIr Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Old Ionic Old Ironsides Related Content Daily Word Quiz: pugilist Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language