/ Dictionary / Index P plot line: Meaning and Definition of Find definitions for: plot' line" Pronunciation: [key] Usually,dialogue that advances the plot, as in a play or motion-picture script. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Plotinus plottage Related Content Daily Word Quiz: feline Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language