Any bipedal dinosaur of the genus Hadrosaurus(noun)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "hadrosaurian" in a sentence
"Stable isotope evidence for changes in dietary niche partitioning among hadrosaurian and ceratopsian dinosaurs of the Hell Creek Formation, North Dakota."
"For an instructive comparison, think of the hadrosaurian dinosaur Maiasaura peeblesorum, which died out about seventy million years ago."