al·​lo·​sau·​rus | \ ˌa-lə-ˈsȯr-əs How to pronounce allosaurus (audio) \

Definition of allosaurus

: any of a genus (Allosaurus) of very large carnivorous North American theropod dinosaurs of the Late Jurassic period

First Known Use of allosaurus

1886, in the meaning defined above

History and Etymology for allosaurus

borrowed from New Latin, genus name, from allo- allo- + -saurus -saurus

Note: Genus name introduced by the American paleontologist Othniel Charles Marsh (1831-99) in "Notice of New Dinosaurian Reptiles from the Jurassic Formation," The American Journal of Science and Arts, vol. 114 (3rd series, vol. 14) (Jul.-Dec., 1877), no. 84, pp. 514-16. The combining element allo- is apparently meant to represent its distinctness: "This genus may be distinguished from any known Dinosaurs by the vertebræ, which are peculiarly modified to ensure lightness" (p. 515).

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The first known use of allosaurus was in 1886

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all·​o·​sau·​rus | \ ˌa-lə-ˈsȯr-əs How to pronounce allosaurus (audio) \

Kids Definition of allosaurus

: a large meat-eating dinosaur related to the tyrannosaur

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to boil down or concentrate

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