bron·​to·​sau·​rus ˌbrän-tə-ˈsȯr-əs How to pronounce brontosaurus (audio)
variants or less commonly brontosaur
: 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 In one scene, the Doctor and Ruby find themselves in the prehistoric era overlooking a lush valley of vegetation, while a brontosaurus and other dinosaurs graze. Jp Mangalindan, Peoplemag, 22 Mar. 2024 Its sprawling brontosaurus of a headquarters building sits just inside Route 128 in Needham, mostly empty on most days. Scott Kirsner,, 11 May 2023 As the glaciers crawl south, refugees, a chilly mammoth, and that lifelike brontosaurus take shelter in their Excelsior, New Jersey, living room. Helen Shaw, Vulture, 25 Apr. 2022 On one hill at a site called Humaca, 11 juvenile sauropods (relatives of the enormous dino commonly known as a brontosaurus) appear to be moving in tandem. Amy Barth, Discover Magazine, 16 Dec. 2010 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

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'brontosaurus.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

1883, in the meaning defined above

Time Traveler
The first known use of brontosaurus was in 1883

Dictionary Entries Near brontosaurus

Cite this Entry

“Brontosaurus.” Dictionary, Merriam-Webster, Accessed 19 Apr. 2024.

Kids Definition


bron·​to·​sau·​rus ˌbränt-ə-ˈsȯr-əs How to pronounce brontosaurus (audio)
variants also brontosaur
: any of several very large four-footed plant-eating dinosaurs

derived from Greek brontē "thunder" and Greek sauros "lizard"

Last Updated: - Updated example sentences
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