n. [ NL., fr. Gr. bronth` thunder + say^ros lizard. ] (Paleon.) a dinosaur of the genus Brontosaurus; an individual may also be called a brontosaurus or an apatosaurus. [ PJC ]

‖n. [ NL., fr. Gr. bronth` thunder + say^ros lizard. ] (Paleon.) A genus of large sauropod American dinosaurs of the jurassic era, or an individual of that genus. A length of sixty feet is believed to have been attained by these reptiles. The genus is also called Apatosaurus, and individuals of the genus are also called brontosaurs. [ 1913 Webster +PJC ]