/ Dictionary / Index P plack: Meaning and Definition of Find definitions for: plack Pronunciation: (plak), [key] — n. a very small copper coin used in Scotland in the 15th and 16th centuries as a four-penny piece. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Placidyl plackart Related Content Daily Word Quiz: apogee Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language