Omphalus, which is also known as navel or umbilicus, is a common anatomical feature that connects a fetus with its mother while in the womb. This term is derived from the Greek word "omphalos," which means "navel." Although omphalus is the most commonly used term for this anatomical feature, there are several other synonyms that also refer to it. Some common synonyms for omphalus include belly button, naval, umbilical cord, and navel string. These terms are all used interchangeably to refer to the small scar-like depression found on the abdomen of most mammals, which marks the site of the former umbilical cord attachment.