Related Clues:

• Referee, to some
• Horned zoo beast, informally
• Swift reptile
• Horned animal
• Gator kin
• Moat menace, briefly
• African heavyweight
• Horse's cousin
• Striped grazer
• Zoo animal
• Hook's nemesis, briefly
• Nile critter
• Thick-skinned jungle beast, briefly
• 'Ice Station ___'
• Thick-skinned mammal