The Atlantic cutlassfish has a compressed, eel-like, silvery body. The body is scaleless and tapers to a slender pointed tail. The fish may appear silvery-white, silvery-gray, or silvery-blue. The fish has a pointed snout and a large underbite with a mouth filled with sharp teeth. The Atlantic cutlassfish’s dorsal fin runs along the entire length of the body. Its pectoral fins are oriented upwards, and it lacks a pelvic, anal, and tail fin. The cutlassfish does have a complete lateral line. The Atlantic cutlassfish typically reaches up to 40 inches in length with longer specimens reaching up to lengths of 7.6 ft.