any of a genus (Triceratops) of massive, four-legged ceratopsian dinosaurs of the Cretaceous having a large, bony crest over the neck, a long horn above each eye, and a short horn on the nose
See triceratops in American Heritage Dictionary 4
(trī-sĕrˈə-tŏpsˌ)
noun
A herbivorous dinosaur of the genus Triceratops, of the Cretaceous Period, having a bony plate covering the neck, a large horn above either eye, and a smaller horn on the nose.