Synonyms for yolk-sac

Noun

1. yolk sac, vitelline sac, umbilical vesicle, vesicula umbilicus, sac

usage: membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional

2. yolk sac, sac

usage: membranous structure enclosing the yolk of eggs in birds reptiles marsupials and some fishes; circulates nutrients to the developing embryo