Definition of ornithischian
: any of an order (Ornithischia) of herbivorous dinosaurs (as a stegosaurus) that have the pubis of the pelvis rotated backward to a position parallel and close to the ischium — compare saurischian
Origin of ornithischian
New Latin Ornithischia, from ornith- + ischium
First Known Use: 1933
Learn More about ornithischian
Britannica.com: Encyclopedia article about "ornithischian"
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