A large, carnivorous, synapsid fossil reptile of the Permian period, with long spines on its back supporting a sail-like crest.
Genus Dimetrodon, order Pelycosauria, subclass Synapsida‘What about the 30-inch dragonflies, six inch cockroaches, and the dimetrodons of the Permian period?’
- ‘I was inhaling ancient molecular effluvia of dimetrodons and plesiosaurs, pterodactyls and tyrannosauruses.’
- ‘But the iguanas in dinosaur costumes, super-sized dimetrodons, superimposed supposed menaces, don't cut it.’
- ‘He also created a pair of pre-dinosaur animals, dimetrodons, now on display at the Las Vegas Natural History Museum.’
- ‘Just yesterday, he glanced up from one of his books and exclaimed, ‘Hey, Mom, this says that dimetrodons were 29 feet long!’’
Modern Latin, from di- ‘twice’ + Greek metron ‘measure’ + odous, odont- ‘tooth’ (taken in the sense ‘two long teeth’).