- an extinct carnivorous mammallike reptile, of the genus Dimetrodon, dominant in North America during the Permian Period, up to 10 feet (3.1 meter) long and usually bearing spinal sails.
Origin of dimetrodon
< New Latin (1878), equivalent to Greek dímetr(os) having two measures (see dimeter) + odṓn tooth; apparently so named in reference to the large size of the anterior incisors relative to the other teeth
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Examples from the Web for dimetrodon
The adductor musculature of the lower jaw in Dimetrodon was divided into lateral and medial groups (Figs. 5, 6).
A similar origin suggests itself for the corresponding muscle, the second major adductor mass, in Dimetrodon.
The dentition of Dimetrodon further substantiates the movement of the jaw in a simple up and down direction.
Watson believed that the jaw of Dimetrodon was capable of anteroposterior sliding.
A comparison of the general pattern of the adductor musculature of Captorhinus and Dimetrodon reveals an expected similarity.
- 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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