iguanodon

/ɪˈɡwɑːnədɑn/
noun
  1. A large plant-eating dinosaur from the early Cretaceous period, known for its thumb spike and upright posture.
    • Scientists believe the iguanodon could walk on two or four legs.
    • Children love learning about the iguanodon because it looks like a giant iguana.
    • The museum's fossil of an iguanodon shows its distinctive thumb spike.