brontosaur

from WordNet (r) 3.0 (2006)

brontosaur
    n 1: huge quadrupedal herbivorous dinosaur common in North
         America in the late Jurassic [syn: {apatosaur},
         {apatosaurus}, {brontosaur}, {brontosaurus}, {thunder
         lizard}, {Apatosaurus excelsus}]

from The Collaborative International Dictionary of English v.0.48

brontosaur \bron`to*saur"\, n. [NL., fr. Gr. bronth` thunder +
   say^ros lizard.] (Paleon.)
   a dinosaur of the genus {Brontosaurus}; an individual may
   also be called a {brontosaurus} or an {apatosaurus}.
   [PJC]

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