Is the tyrannosaurus rex a therapod or a saurapod?

Theropods were two legged, carnivorous dinosaurs. Triceratops had four legs and was an herbivore. Therefor, Triceratops wasn't a theropod. Instead, they were a type of ceratopsian, which were four legged, herbivorous dinosaurs with a beak and usually a frill and often horns.