Any of various herbivorous bipedal ornithischian dinosaurs of the group Pachycephalosauria of the Cretaceous Period, having a very thick skull and a beaked mouth. Also called pachycephalosaur.
[From New Latin Pachycephalosauria, group name, from Pachycephalosaurus, type genus; see PACHYCEPHALOSAURUS.]
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Indo-European & Semitic Roots Appendices
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