(also hadrosaurus /ˌhadrəˈsôrəs/)
- a large, herbivorous, mainly bipedal dinosaur of the middle to late Cretaceous period, with jaws flattened like the bill of a duck. Also called duck-billed dinosaur.
- Family Hadrosauridae, infraorder Ornithopoda, order Ornithischia
late 19th century: from modern Latin Hadrosaurus (genus name), from Greek hadros 'thick, stout' + sauros 'lizard'