/ Dictionary / Index P plate glass: Meaning and Definition of Find definitions for: plate' glass' Pronunciation: [key] a soda-lime-silica glass formed by rolling the hot glass into a plate that is subsequently ground and polished, used in large windows, mirrors, etc. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. plate girder plateholder Related Content Daily Word Quiz: simian Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language