Breadcrumb Home > Thesaurus > A Synonyms of amnion Find synonyms for: Noun 1. amnion, amniotic sac, amnios, sac usage: thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals) WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of amnion (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Chinese New Year History, Meaning, and Celebrations Current Events This Week: February 2024 Valentine's Day Valentine's Day History Mardi Gras 30 "Charlie and the Chocolate Factory" Quotes ✖ Related Content Daily Word Quiz: inchoate Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language