/ Dictionary / Index I iron horse: Meaning and Definition of Find definitions for: i'ron horse' Pronunciation: [key] — Older Use. Older Use. a locomotive. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. iron-hearted ironic Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language