The word "funis" refers to a thick, cord-like structure that connects an embryo or fetus to the placenta. There are several synonyms for this word, including umbilical cord, navel string, and vitelline duct. The umbilical cord is the most commonly used term and is derived from the Latin word "umbilicus," meaning navel. The navel string is another term used to describe this organ. The vitelline duct refers specifically to the part of the funis that connects to the yolk sac in early embryonic development. Regardless of the synonym used, the funis serves a crucial role in fetal development by providing nutrients and oxygen to the developing baby and disposing of waste products.