Definition that contains ampre
- suborder petromyzoniformes lampreys as distinguished from hagfishes
- order cyclostomata primitive jawless aquatic vertebrate: lampreys; hagfishes
- family petromyzontidae lampreys
- suborder hyperotreta hagfishes as distinguished from lampreys
- myxiniformes hagfishes as distinguished from lampreys
- superclass agnatha superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct forms
- petromyzon typical lampreys
- petromyzontidae lampreys
- genus petromyzon typical lampreys
- suborder myxiniformes hagfishes as distinguished from lampreys