‖n. pl. [ Nl. See Testudo. ] (Zool.) An order of reptiles which includes the turtles and tortoises. The body is covered by a shell consisting of an upper or dorsal shell, called the carapace, and a lower or ventral shell, called the plastron, each of which consists of several plates. [ 1913 Webster ]

{ } a. [ L. testudinatus, fr. testudo, -inis, a tortoise, an arch or vault. ] Resembling a tortoise shell in appearance or structure; roofed; arched; vaulted. [ 1913 Webster ]