Definition of Testudines in US English:


plural noun

  • An order of reptiles which comprises the turtles, terrapins, and tortoises. They are distinguished by having a shell of bony plates covered with horny scales, and many kinds are aquatic.

    Also called (especially formerly) Chelonia
    • ‘In terms of molecular structure, the researchers found the order Testudines to be closely related to the more recently evolved order Crocodilia.’
    • ‘Most likely, Testudines progressed in a unique evolutionary direction.’
    • ‘The first formal use of the word Testudines as a taxon name can be found in Batsch.’
    • ‘All these taxa are relevant to the history of the conquest of land by vertebrates because they are outside the large clades of extant tetrapods (Apoda, Caudata, Anura, Mammalia, Testudines, Sauria).’
    • ‘All turtles are placed within the order Testudines.’


Modern Latin (plural), based on Latin testa ‘shell’.