/ Dictionary / Index P post-office box: Meaning and Definition of Find definitions for: post'-office box" Pronunciation: [key] (in a post office) a locked compartment into which the mail of a box renter is put to be called for. Abbr.: POB, P.O.B. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. post office Post Office Department Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language