Tyrannosaurus means 'tyrant lizard'. It roamed freely, nearly 68 million years ago, in modern day North America. Tyrannosaurus lived along with the other tyrannosaurids. Tyrannosaurus was a two legged meat eating dinosaur that had a massive skull and a long and heavy tail. Its forelimbs were smaller incomparison to its large and powerful hindlimbs. The Tyrannosaurus is the largest known tyrannosaurid and probably the largest land predator too. It was 43 feet in length and nearly 6.8 tons in weight.

Tyrannosaurus was one of the largest land carnivores. It had a s-shaped neck and was relatively short with a huge amount of muscules. Its forelimbs had only two digits each. The hind limbs were long. The tail of the Tyrannosaurus was heavy, with a count of vertebrae that exceeds forty. This feature enabled the structure to balance both its torso and its big head. The Tyrannosaurus' skull was distinctly different from the other large theropods, and as such was quiet wide on the rear side, but had a somehow narrow snout.

The Tyrannosaurus had a good vision. Its skull bones were large in volume, and its nasals and other amount of bones were somehow fused together, making them quiet rigid. Tyrannosaurus had a very powerful bite. Its upper jaw was shaped like the U letter (versus the usual V shape), and this significantly helped the dinosaur to rip the prey's bones and tissue apart with quiet often a single bite.