Definition that contains chordate
- notochord a flexible rodlike structure that forms the supporting axis of the body in the lowest chordates and lowest vertebrates and in embryos of higher vertebrates
- genus appendicularia a genus of chordates in the class Larvacea
- superclass agnatha superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct forms
- agnatha superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct forms