Bar·​o·​sau·​rus ¦ber-ə-¦sȯr-əs How to pronounce Barosaurus (audio)
: a genus of very large, herbivorous, sauropod dinosaurs (family Diplodocidae) that lived during the late Jurassic period, closely resemble the related Diplodocus dinosaurs, and may have attained a length of up to 90 feet (27 meters) with a neck length of 30 feet (9.1 meters)
… advanced the peculiar idea that the long-necked Barosaurus needed eight hearts to pump enough blood to its head.Paul Hoffman, Discover, January 1993
barosaurus or less commonly barosaur
¦ber-ə-¦sȯr How to pronounce Barosaurus (audio)
, plural barosauruses or less commonly barosaurs : a dinosaur of the genus Barosaurus
A five-story barosaurus is rearing up to protect her baby barosaurus and to smash a marauding allosaurus with a nasty overbite.Leslie Camhi, Village Voice, 26 July 1994
If the barosaur couldn't rear up on its hind legs, how did it defend itself?Jack Hitt, Discover, September 2006

Word History


borrowed from New Latin, from baro- baro- + -saurus -saurus

Note: Genus name introduced by the American paleontologist Othniel Charles Marsh (1831-99) in "Description of New Dinosaurian Reptiles," American Journal of Science, 3rd series, vol. 39 (January-June, 1890), p. 85. Marsh does not disclose any justification for the name, though if the intent was to coin the Greco-Latin equivalent of "heavy lizard," bary- would have been the apter element. The neuter s-stem báros, "weight, heavy weight, heaviness," was not a source of compounds in classical Greek, and owes its use in modern scientific terminology to baroscope and barometer, from which the meaning "pressure" has been extrapolated.

First Known Use

1890, in the meaning defined at sense 1

Time Traveler
The first known use of Barosaurus was in 1890

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Cite this Entry

“Barosaurus.” Dictionary, Merriam-Webster, Accessed 30 May. 2024.

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