Chorda dorsalis is a medical term that refers to a string-like structure in the anatomy of certain animals. This structure is commonly found in the anatomy of fish, particularly in the anatomy of their spinal cords. It is known by many different synonyms, including notochord, flexible rod, notochordal rod, or notochordal process. Similarly, in human fetuses, the chorda dorsalis is also known as the notochord. This structure plays an important role in the development of the vertebrate embryo, providing structural support and signaling for the developing nervous system. While the term chorda dorsalis is commonly used in medical and scientific literature, its various synonyms are often used interchangeably and can be used to describe this important anatomical feature.