bron·to·saur·us

[New Latin Brontosaurus, former genus name : Greek brontē, thunder + Greek sauros, lizard.]

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

brontosaurus

brontosaur

[C19: from New Latin, from Greek brontē thunder + sauros lizard]

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

bron•to•sau•rus

Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

bron·to·sau·rus

Word History Take a little deception, add a little excitement, stir them with a century-long mistake, and you have the mystery of the brontosaurus. Specifically, you have the mystery of its name. For 100 years this 70-foot-long, 30-ton vegetarian giant had two names. This case of double identity began in 1877, when bones of a large dinosaur were discovered. The creature was dubbed apatosaurus, a name that meant "deceptive lizard" or "unreal lizard." Two years later, bones of a larger dinosaur were found, and in all the excitement, scientists named it brontosaurus or "thunder lizard." This name stuck until scientists decided it was all a mistake—the two sets of bones actually belonged to the same type of dinosaur. Since it is a rule in taxonomy that the first name given to a newly discovered organism is the one that must be used, scientists have had to use the term apatosaurus. But "thunder lizard" had found a lot of popular appeal, and many people still prefer to call the beast brontosaurus.

The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.