Definition of edaphosaur in English:

noun

• A large herbivorous synapsid reptile of the late Carboniferous and early Permian periods, with long knobbly spines on its back supporting a sail-like crest.

  Genus Edaphosaurus, order Pelycosuria, subclass Synapsida

  ‘Along with the Diadectidae, Edaphosaurus is one of the earliest known plant-eating tetrapods (land-living vertebrates).’

  ‘Other Edaphosauruses were not so large and some were half a meter or less in length.’