or·​nith·​is·​chi·​an ˌȯr-nə-ˈthi-skē-ən How to pronounce ornithischian (audio)
: any of an order (Ornithischia) of herbivorous dinosaurs (such as a stegosaurus) that have the pubis of the pelvis rotated backward to a position parallel and close to the ischium compare saurischian
ornithischian adjective

Example Sentences

Recent Examples on the Web The dinosaur, first described in 2015 as a bizarre, herbivorous theropod, is actually a primitive ornithischian, according to the study — a placement that would strengthen the authors’ argument for rewriting the entire family tree. Jon Tennant, Discover Magazine, 23 Jan. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ornithischian.' 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 Ornithischia, from ornith- + ischium

First Known Use

1888, in the meaning defined above

Time Traveler
The first known use of ornithischian was in 1888

Dictionary Entries Near ornithischian

Cite this Entry

“Ornithischian.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ornithischian. Accessed 4 Jun. 2023.

More from Merriam-Webster on ornithischian

Love words? Need even more definitions?

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