/ Thesaurus / H Synonyms of hadrosaurus Find synonyms for: Noun1. hadrosaur, hadrosaurus, duck-billed dinosaur, ornithischian, ornithischian dinosaurusage: any of numerous large bipedal ornithischian dinosaurs having a horny duck-like bill and webbed feet; may have been partly aquaticWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: nefarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language