/ Dictionary / Index P plinth block: Meaning and Definition of Find definitions for: plinth' block" Pronunciation: [key] a plinth interrupting a door or window architrave at the floor or ground level. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. plinth Pliny Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language