/ Dictionary / Index O on-line catalog: Meaning and Definition of Find definitions for: on'-line cat'alog Pronunciation: [key] a bibliographic record of a library's holdings, available in machine-readable form. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. on-line onlooker Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language