/ Thesaurus / V Synonyms of vesicula umbilicus Find synonyms for: Noun1. yolk sac, vitelline sac, umbilical vesicle, vesicula umbilicus, sacusage: membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functionalWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: panacea Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language