/ Dictionary / Index P postilion: Meaning and Definition of Find definitions for: pos•til•ion Pronunciation: (pō-stil'yun, po-), [key] — n. a person who rides the left horse of the leading or only pair of horses drawing a carriage. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: postilion (Thesaurus) posticum Post-Impressionism Related Content Daily Word Quiz: designate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language