brachiosaur

noun

brach·​i·​o·​saur ˈbra-kē-ō-ˌsȯr How to pronounce brachiosaur (audio)
: any of a genus (Brachiosaurus) of very large sauropod dinosaurs of the Late Jurassic period having a massive body, a very long neck, and forelegs longer than hind legs

Word History

Etymology

New Latin Brachiosaurs, from brachi- + Greek sauros lizard

First Known Use

1912, in the meaning defined above

Time Traveler
The first known use of brachiosaur was in 1912

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Cite this Entry

“Brachiosaur.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brachiosaur. Accessed 5 Jul. 2026.

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