ceratopsian

noun

1. 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.

1. 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.