Testudo

Testudo (which meant "tortoise" in classical Latin) may refer to:

• Testudo (genus), a genus of tortoises
• Testudo (lyre), the Latin variant of the Greek chelys harp, involving a sound-box made from a tortoise shell
• The testudo formation, a Roman military tactic, where a formation of soldiers used their shields to form a tortoise-shell-like protective cover against incoming missiles
• Battering ram, an armored siege engine of antiquity, with metal plating on the top to protect from missiles fired from above
• The name of the official mascot of the University of Maryland, College Park, a diamondback terrapin
• Testudo - Pisces (constellation)#Asterisms and subdivison, an obsolete constellation now in the constellation of Pisces
• Testudo, an alternative name of the constellation Lyra