any of a superfamily (Sauropoda) of gigantic, plant-eating, four-footed saurischian dinosaurs with a long neck and tail, five-toed limbs, and a small head, as an apatosaurus
adjective
of the sauropods
See sauropod in American Heritage Dictionary 4
(sôrˈə-pŏdˌ)
noun
Any of various large semiaquatic saurischian dinosaurs of the suborder Sauropoda, of the Jurassic and Cretaceous periods.