what is dinosaur what is the dinosaur meaning Share with your friends Share 0 Keanu Vaz answered this A dinosaur is a fossile of the mesozoic era of enormous size and the word Dinosaur means terrible lizard dino (terrible) and saur (lizard) 1 View Full Answer Anushree . K answered this Dinosaur was a diverse group of reptiles of the clade dinosauria. Now they are extinct in the world 1