∞ generated and posted on 2016.01.01 ∞
Especially carnivorous, bipedal dinosaurs along with their bird descendants.
Picture in particular such dinosaurs as Tyranosaurus rex and Velociraptor, though not all theropods were quite that superlative.
The theropods, along with dinosaurs generally, were archosaurs.
The theropods more specifically were saurischian or 'lizard-hipped dinosaurs', contrasting the ornithischian or 'bird-hipped dinosaurs'. Note, nonetheless that it is the lizard-hipped dinosaurs that are ancestral to the birds, making these 'bird' hips in the ornithischian case an example of convergent evolution.