[dahy-nuh-sawr] 
| 1. | any chiefly terrestrial, herbivorous or carnivorous reptile of the extinct orders Saurischia and Ornithischia, from the Mesozoic Era, certain species of which are the largest known land animals. |
| 2. | something that is unwieldy in size, anachronistically outmoded, or unable to adapt to change: The old steel mill was a dinosaur that cost the company millions to operate. |
| di·no·saur (dī'nə-sôr') n.
[New Latin Dīnosauria, group name, from Dīnosaurus, former genus name : Greek deinos, monstrous + Greek sauros, lizard.] di'no·sau'ric (-sôr'ĭk) adj. |
Reptiles, now extinct, that were the dominant life form on Earth for many millions of years. The name dinosaur comes from the Greek words for “monstrous lizard.” Dinosaurs became extinct suddenly, about sixty-five million years ago. Scientists now believe that their extinction was caused by the impact of a large asteroid on the Earth.
Note: Some dinosaurs were very large and had small brains — factors that may in part have led to their extinction. The term is often used to refer to something or someone that is antiquated and unable to adapt to change: “The old cavalry generals couldn't adjust to the use of tanks — they became dinosaurs.”
Note: Commonly known dinosaurs include Tyrannosaurus rex, Brontosaurus, Stegosaurus, and Triceratops.
Note: Some scientists believe that modern birds are the descendants of dinosaurs.
nəˌsɔr
