4 days ago · Dinosaur, the common name given to a group of reptiles, often very large, that first appeared roughly 245 million years ago and thrived worldwide for nearly 180 million years.

4 days ago · Dinosaur - Extinction, Fossils, Evolution: Dinosaurs lived in many kinds of terrestrial environments, and although some remains, such as footprints, indicate where dinosaurs actually …

Dinosaur, the common name given to a group of reptiles, often very large, that first appeared roughly 245 million years ago (near the beginning of the Middle Triassic Epoch) and thrived worldwide for …

4 days ago · Dinosaur - Evolution, Classification, Extinction: After dinosaurs were recognized as a new type of fossil animal, popular fascination with them reached a peak in the 1850s with the first …

Dec 22, 2025 · Dinosaur - Reptiles, Extinction, Fossils: The chief difference between the two major groups of dinosaurs is in the configuration of the pelvis. The two dinosaurian orders were named …

dinosaur, Any of the extinct reptiles that were the dominant land animals during most of the Mesozoic Era (251–65.5 million years ago).

4 days ago · Dinosaur - Extinction Causes, Evidence, & Theory: The mass extinction of dinosaurs 66 million years ago remains a misconception; the fossil record shows that dinosaurs were already in …

4 days ago · Dinosaurs are currently defined as Triceratops (representing Ornithischia), birds (representative of Saurischia), and all the descendants of their most recent common ancestor. …

Britannica Editors. "6 Awesome Dinosaur Species You Should Know". Encyclopedia Britannica, 13 Jun. 2025, https://www.britannica.com/list/6-awesome-dinosaur-species-you-should-know.

These lizardlike reptiles got the name dinosaur from Greek words that mean “terrible lizard.” The last dinosaurs became extinct, or died out, about 65.5 million years ago.