any very large herbivorous quadrupedal dinosaur of the genus Apatosaurus, common in North America during Jurassic times, having a long neck and long tail: suborder Sauropoda (sauropods)
Formerly called: brontosaurus
Word origin
C19: from New Latin, from Greek apatē deceit + sauros lizard
apatosaurus in American English
(əˌpætəˈsɔrəs; ˌ æpətəˈsɔrəs)
noun
any of a genus (Apatosaurus) of huge sauropod dinosaurs of the Late Cretaceous, weighing more than 18,000 kg (20 tons)