dimetrodon

American  

[dahy-me-truh-don] / daɪˈmɛ trəˌdɒn /

noun

1. an extinct carnivorous mammallike reptile, of the genus Dimetrodon, dominant in North America during the Permian Period, up to 10 feet (3.1 meters long and usually bearing spinal sails.

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dimetrodon Scientific  

/ dī-mĕt′rə-dŏn′ /

1. An extinct, carnivorous reptile of the genus Dimetrodon of the Permian Period having a body similar to an alligator's but with a tall, curved sail on its back. The sail had a thick network of blood vessels and may have been used to regulate the animal's body temperature. The dimetrodon belonged to the synapsids, an early group of reptiles that was ancestral to mammals.

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Etymology

Origin of dimetrodon

From New Latin (1878), equivalent to Greek dímetr(os) “having two measures” ( dimeter ) + odṓn “tooth”; apparently so named in reference to the large size of the anterior incisors relative to the other teeth

Example Sentences

The main culprits are marine reptiles like mosasaurs, plesiosaurs, ichthyosaurs; flying reptiles like pterodactyls; and the sail-backed dimetrodon, which is actually more closely related to humans than dinosaurs.

From New York Times

Meals include “shaved rabbit’s foot caviar necklace, in a bowl,” a four-course dinner contained in concentric balloons made from the “notoriously elastic dimetrodon bladder,” and spring rolls made out of an evil stepsister.

From Los Angeles Times