|brachiosaurus (brā'kē-ə-sôr'əs) or brachiosaur (brā'kē-ə-sôr'əs) Pronunciation Key
A very large sauropod dinosaur of the genus Brachiosaurus of the Jurassic and Cretaceous Periods. It had forelegs that were longer than its hind legs, and nostrils on top of its head.
any member or relative of the dinosaur genus Brachiosaurus, which lived 150 million to 130 million years ago from the Late Jurassic to the Early Cretaceous Period. Brachiosaurs were the heaviest and tallest sauropod dinosaurs for which complete skeletons exist; larger fossil bones belonging to other (and possibly related) sauropods have been found, but these specimens are incomplete. Fossilized remains of brachiosaurs are found in Africa, North America, and Europe.
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