Definition of labyrinthodont in US English:



  • 1(of teeth) having the enamel deeply folded to form a labyrinthine structure.

    1. 1.1 Relating to a group of large fossil amphibians of the late Devonian to early Triassic periods having labyrinthodont teeth.
      • ‘Different labyrinthodont lineages gave rise to all the other tetrapods.’
      • ‘Whether it was a labyrinthodont amphibian or a primitive reptile has been much disputed.’
      • ‘It is thought that in other parts of the world competition from crocodiles wiped out most labyrinthodont species.’
      • ‘On land there was a major faunal turnover in which labyrinthodont amphibians, early reptile groups, and mammal-like reptiles died out and were replaced by archosaurs, lepidosaurs, and mammals.’
      • ‘Finding labyrinthodont amphibian vertebrae and lungfish teeth, we took several bags of matrix to wash.’


  • A labyrinthodont amphibian.

    Former subclass Labyrinthodontia: several families, but no longer considered to be a single group

    • ‘The labyrinthodonts, parareptiles and theromorphs were among the most ancient tetrapods.’
    • ‘Then in the seventies an almost complete fossil of another labyrinthodont turned up in rocks that were definitely much younger than 250 million years old.’
    • ‘All of these Palaeozoic and early Mesozoic amphibians are called labyrinthodonts and lepospondyls, based on features of their teeth and vertebrae.’
    • ‘Two main types of early amphibians include the large powerfully built labyrinthodonts and the small, slender lepospondyls.’
    • ‘Curiously, labyrinthodonts are not found in the Otways - crocodiles apparently filled the same ecological niche.’


Mid 19th century: from modern Latin Labyrinthodontia, from Greek laburinthos ‘labyrinth’ + odous, odont- ‘tooth’.