1. An extinct synapsid reptile from the Permian period, characterized by a large sail-like structure on its back formed by elongated spinal processes.
Usage: paleontology; often capitalized as a genus name

Examples

• Dimetrodon was one of the largest predators of its time during the early Permian period.
• The distinctive sail on a dimetrodon's back may have been used for thermoregulation or display.
• Fossils of dimetrodon have been found in North America and Europe.
• Scientists believe dimetrodon was more advanced than typical reptiles of its era.
• The sail-backed dimetrodon is often confused with the dinosaur Spinosaurus, though they lived in different periods.