bron·​to·​sau·​rus | \ ˌbrän-tə-ˈsȯr-əs How to pronounce brontosaurus (audio) \
variants: or less commonly brontosaur \ ˈbrän-​tə-​ˌsȯr How to pronounce brontosaurus (audio) \

Definition of brontosaurus

: any of a genus (Apatosaurus) of very large sauropod dinosaurs of the Late Jurassic : apatosaurus

Note: The name brontosaurus continues to be commonly used for these dinosaurs even though their former genus name (Brontosaurus) is considered invalid.

Examples of brontosaurus in a Sentence

Recent Examples on the Web Sauropods' species include the popularized brontosaurus and were known for their long necks and tails. Scott Gleeson, USA TODAY, 20 July 2022 On one side, there’s a T-rex that is 30 feet tall, on the other side is a brontosaurus that is 39 feet tall. Sheryl Devore,, 26 Apr. 2021 The latest attraction at the Volo Auto Museum is not a car — but a dinosaur, actually dozens of animatronic dinosaurs including a 30-foot-tall Tyrannosaurus rex and a 35-foot tall brontosaurus. Sheryl Devore,, 26 Apr. 2021 Ultimately, only two were built: a 45-foot-tall, 150-foot-long brontosaurus and a Tyrannosaurus rex named Mr. Rex. Los Angeles Times, 23 Mar. 2021 For years after the park closed, the skeleton of the Big Plunge towered over I-25 like the neck of a brontosaurus. Rachel Syme, The New Yorker, 10 Sep. 2020 Two full-figured men snacking on brontosaurus burgers, married to women with waists that are the same size as their necks. Katie Musgrave,, 20 May 2020 An orphaned brontosaurus teams up with other young dinosaurs in order to reunite with their families in a valley. Ben Flanagan |, al, 16 Mar. 2020 Trip skids across the floor at Hinkle Fieldhouse before games, finding his brontosaurus-sized bone and standing with it in front of the Butler bench seconds before tipoff. Gregg Doyel, Indianapolis Star, 22 Jan. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'brontosaurus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of brontosaurus

1883, in the meaning defined above

History and Etymology for brontosaurus

New Latin, from Greek brontē thunder + sauros lizard; akin to Greek bremein to roar

Learn More About brontosaurus

Time Traveler for brontosaurus

Time Traveler

The first known use of brontosaurus was in 1883

See more words from the same year

Dictionary Entries Near brontosaurus




See More Nearby Entries 

Statistics for brontosaurus

Cite this Entry

“Brontosaurus.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

More Definitions for brontosaurus


bron·​to·​sau·​rus | \ ˌbrän-tə-ˈsȯr-əs How to pronounce brontosaurus (audio) \

Kids Definition of brontosaurus

: a huge plant-eating dinosaur with a long neck and tail and four thick legs


Test Your Vocabulary

Challenging Words You Should Know

  • hedgehog reading a book
  • Often used to describe “the march of time,” what does inexorable mean?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!