/ Dictionary / Index O old chap: Meaning and Definition of Find definitions for: old" chap' Pronunciation: [key] — Chiefly Brit. Chiefly Brit. (used in informal direct address). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Old Catholic Old Church Slavonic Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language