noun
- any of several four-footed, herbivorous dinosaurs of the suborder Ceratopsia, of the late Cretaceous Period, having an enlarged skull with a beak, a large perforated frill at the back, and, in some species, one or three horns.
- Any of various dinosaurs of the group Ceratopsia of the late Jurassic and Cretaceous Periods. Ceratopsians were ornithischians characterized by skulls with a parrotlike beak, a broad bony frill extending back over the neck, and often one or more horns. Most ceratopsians walked on all fours and grew to medium or large size. Triceratops was a ceratopsian.