Tyrannosaurus (tie- ran-oh-sore-us) means "Tyrant lizard." Tyrannosaurus, species name rex, remains the most popular of all dinosaurs. It was among the largest land predators that ever lived and was certainly one of the most dangerous. It had a 4 foot long skull, 8 inch long serrated teeth, stereoscopic vision and long birdlike legs. Tyrannosaurus had jaws that were extremely powerful, with thousands of pounds of pressure per square inch to crush the bones of prey.