/ Thesaurus / P Synonyms of proscenium arch Find synonyms for: Noun1. proscenium arch, archusage: the arch over the opening in the proscenium wallWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: pristine Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language