Wiktionary
n. An informal name for ornithopod dinosaurs of the family Hadrosauridae derived from the similarity of the heads of certain members of that family to those of modern ducks.
WordNet
n. any of numerous large bipedal ornithischian dinosaurs having a horny duck-like bill and webbed feet; may have been partly aquatic [syn: hadrosaur, hadrosaurus]
Usage examples of "duck-billed dinosaur".
The area beyond the elevator was filling up with prehistoric creatures: a duck-billed dinosaur, an Eryops, an ancient tortoise, all moving rather stiffly, like people in tuxedos entering a subway car.
Who else but Cal would care whether the body of a duck-billed dinosaur washed out one side of the mountain or the other?
From what little is known now, it is thought to have belonged to a hadrosaur, a large duck-billed dinosaur.