Breadcrumb Home > Thesaurus > P Synonyms of peritoneum Find synonyms for: Noun1. peritoneum, serous membrane, serosausage: a transparent membrane that lines the abdominal cavity in mammals and covers most of the visceraWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of peritoneum (Dictionary) ✖ Related Content Daily Word Quiz: sepulture Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language