Class Chondrichthyes is a group of cartilaginous fish that includes sharks, rays, and chimaeras. There are several synonyms that are used to describe this class, including cartilaginous fish, elasmobranchs, and selachimorpha. Cartilaginous fish refers to the fact that these animals have a skeleton made of cartilage instead of bone, while elasmobranchs is a broad term that specifically refers to sharks and rays. The name Selachimorpha is derived from the Greek word "selachos," meaning shark, and "morph," meaning form. This name accurately describes the group's prominent feature - having a body shaped like a torpedo. These names, therefore, tell us about the characteristics of the group and their classification.