a·pat·o·saur·us (ə-păt′ə-sôrəs) or a·pat·o·saur (ə-pătə-sôr′)
A very large herbivorous sauropod dinosaur of the genus Apatosaurus of the Jurassic Period, having a long neck and tail and a small head.
[New Latin Apatosaurus, unreal lizard, genus name : Greek apatē, untruth, lie + Greek sauros, lizard.]
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