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Related to dimetrodon: edaphosaurus
Any of various carnivorous pelycosaurs of the genus Dimetrodon of the Permian Period, having long spines on the back that supported a sail-like structure, and powerful jaws with sharp teeth.
an extinct carnivorous mammallike reptile of the North American Permian genus Dimetrodon, with high spines along the back.
[< New Latin (1878) = Greek dímetr(os) having two measures (see dimeter) + odṓn tooth]
An extinct, meat-eating reptile 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 early group of reptiles that many scientists believe was ancestral to mammals.