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Webster 1913 Edition
Brontotherium
‖
Bronˊto-the′ri-um
,Noun.
[NL., fr. Gr. [GREEK] thunder + [GREEK] beast.]
(Paleon.)
A genus of large extinct mammals from the miocene strata of western North America. They were allied to the rhinoceros, but the skull bears a pair of powerful horn cores in front of the orbits, and the fore feet were four-toed. See Illustration in Appendix.