pachycephalosaur
/ˌpækɪˈsɛfələsɔr/
noun
- A small, plant-eating dinosaur from the Cretaceous period, known for its very thick, bony skull dome.
- Fossils of a pachycephalosaur were discovered in the badlands of Montana.
- The pachycephalosaur used its thick skull to head-butt rivals during mating season.
- Unlike the larger pachycephalosaurus, this pachycephalosaur was only about the size of a large dog.