stegosaur

American  

[steg-uh-sawr] / ˈstɛg əˌsɔr /

noun

1. a plant-eating dinosaur of the genus Stegosaurus, from the Jurassic and Cretaceous periods, having a heavy, bony armor and a row of bony plates along its back, and growing to a length of 20 to 40 feet (6–12 meters).

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stegosaur British  

/ ˈstɛɡəˌsɔː, ˌstɛɡəˈsɔːrəs /

noun

1. any quadrupedal herbivorous ornithischian dinosaur of the suborder Stegosauria, esp any of the genus Stegosaurus, of Jurassic and early Cretaceous times, having an armour of bony plates

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stegosaur Scientific  

/ stĕg′ə-sôr′ /

1. Any of several large herbivorous ornithischian dinosaurs of the group Stegosauria of the Jurassic and early Cretaceous Periods. The largest genus, Stegosaurus, had a tail with two horizontal spikes for defense, and an arched back with an alternating double row of large, triangular, upright bony plates. Stegosaurs grew over 6 m (20 ft) long, but had extremely small heads with brains the size of a walnut. The hindquarters were controlled by a neural ganglion in the hip region that was larger than the brain.

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Etymology

Origin of stegosaur

< New Latin Stegosaurus (1877); see stego-, -saur

Explanation

A stegosaur was a dinosaur with hard, bony plates all along its back. You can see a stegosaur skeleton at the American Museum of Natural History. This large, armored, plant-eating of dinosaur is also known as stegosaurus. Most stegosaurs had tails with sharp spikes that they used to defend themselves from predators, and most of them lived in the Northern Hemisphere, mainly in the area that today makes up North America. The name comes from the Greek stegos, "a roof or covering," which describes stegosaur's protective plates.

Example Sentences

The researchers say Neostegosauria includes medium and large stegosaur species that lived across several continents during different periods of the Jurassic and Early Cretaceous.

From Science Daily • May 17, 2026

The fossil is considered the best-preserved stegosaur skull ever discovered in Europe, a remarkable achievement because dinosaur skulls are extremely delicate and rarely survive intact over millions of years.

From Science Daily • May 17, 2026

In 2000 he was part of the team that discovered the first stegosaur fossils outside North America.

From Los Angeles Times • Aug. 19, 2022

Examples: the Asian spinosaurid Ichthyovenator, the Chinese stegosaur Wuerhosaurus/Stegosaurus homheni.

From Scientific American • Apr. 22, 2013

“It was my husband who first identified the fossilized stegosaur droppings for the university.”

From "Linked" by Gordon Korman