Meet the Megalosaurus, the name given to the 1st dinosaur 200 years ago

Tuesday marks the 200th anniversary of the first dinosaur ever named, which changed the field of paleontology: The Megalosaurus.

The dinosaur was named by William Buckland, a professor of geology at the University of Oxford, who discovered fossil remains at Stonesfield, a village in Oxfordshire about 10 miles northwest of Oxford.

Mistaking them for the bones of a giant lizard, he named the animal Megalosaurus, combining the Greek words "megas" meaning "big" or "great" and "sauros" meaning "lizard."

Buckland's description of the first non-avian dinosaur on Feb. 20, 1824, was presented at a meeting of the Geological Society, an organization made of earth and planetary scientists.

Dr. Paul Sereno, a paleontologist at the University of Chicago, said dinosaur bones and teeth have been found for centuries, and even in pre-historic times, but nobody knew what a dinosaur was at the beginning of the 19th century.

"A lot of people don't understand that you don't typically find a dinosaur altogether in a skeleton that looks like it's just ready to mount in a museum," he told ABC News. "You usually find pieces that are very difficult to understand what they represent and that's why it took so long for dinosaurs to enter the field even though fossils had been known for hundreds of years earlier."

At the time, the Megalosaurus was viewed as a large reptile. The term "dinosaur", meaning "terrible lizard," wasn't even coined until 18 years later by Sir Richard Owen.

"When this thing was named, there were no dinosaurs, so they named it as a species of lizard," Dr. David Burnham, a paleontologist at the University of Kansas Biodiversity Institute and Natural History Museum, told ABC News. "So, of course, they reconstructed it like a four-legged reptile. However, they had no idea how to make a size estimate, how big the animal was, because they were missing so many parts to the skeleton."

Scientists believed the Megalosaurus was about 65 feet (20 meters) long and walked on four legs. However, more recent estimates show the animal was actually about 20 feet (6 meters) long and walked on two legs.

Megalosaurus was a carnivore that lived in the Middle Jurassic period, between 165 to 168 million years ago.

To mark the event, the Geological Society is hosting a number of events including a lecture on the changing views of dinosaurs over the last 200 years. The Society has also installed a life-sized replica of a skeleton of a Megalosaurus that can be viewed until Feb. 29.

The Oxford Museum of Natural History has been hosting tours of "Megalosaurus and Buckland treasures" in addition to an exhibit of Buckland's work in October.

Burnham said that milestones such as the naming of the Megalosaurus are important to commemorate because it represents how far the field of paleontology has advanced.

Sereno agrees and says since Buckland's time, new types of dinosaurs have been uncovered at an increasing pace due to the growing number of paleontologists and growing understanding among the general public about what a dinosaur looks like.

"As a result, we're learning and naming more dinosaurs today than ever before," he said. "We've really begun to sort out the dinosaur family tree, sort out their physiology and lots of other details, and we're going to learn a lot more in the decades to come."